Adjust libsanitizer to ABI change in glibc 2.31.

Adapted to 3.x from this upstream commit:
https://github.com/llvm/llvm-project/commit/947f9692440836dcb8d88b74b69dd379d85974ce

diff --git a/lib/sanitizer_common/sanitizer_platform_limits_posix.cc b/lib/sanitizer_common/sanitizer_platform_limits_posix.cc
--- a/lib/sanitizer_common/sanitizer_platform_limits_posix.cc
+++ b/lib/sanitizer_common/sanitizer_platform_limits_posix.cc
@@ -1130,8 +1130,9 @@ CHECK_SIZE_AND_OFFSET(ipc_perm, cgid);
 #ifndef __GLIBC_PREREQ
 #define __GLIBC_PREREQ(x, y) 0
 #endif
-#if !defined(__aarch64__) || !SANITIZER_LINUX || __GLIBC_PREREQ (2, 21)
-/* On aarch64 glibc 2.20 and earlier provided incorrect mode field.  */
+#if !SANITIZER_LINUX || __GLIBC_PREREQ (2, 31)
+/* glibc 2.30 and earlier provided 16-bit mode field instead of 32-bit
+   on many architectures.  */
 CHECK_SIZE_AND_OFFSET(ipc_perm, mode);
 #endif
 
diff --git a/lib/sanitizer_common/sanitizer_platform_limits_posix.h b/lib/sanitizer_common/sanitizer_platform_limits_posix.h
--- a/lib/sanitizer_common/sanitizer_platform_limits_posix.h
+++ b/lib/sanitizer_common/sanitizer_platform_limits_posix.h
@@ -188,17 +188,16 @@ namespace __sanitizer {
     unsigned __seq;
     u64 __unused1;
     u64 __unused2;
-#elif defined(__mips__) || defined(__aarch64__)
-    unsigned int mode;
-    unsigned short __seq;
-    unsigned short __pad1;
-    unsigned long __unused1;
-    unsigned long __unused2;
+#elif defined(__sparc__)
+  unsigned mode;
+  unsigned short __pad2;
+  unsigned short __seq;
+  unsigned long long __unused1;
+  unsigned long long __unused2;
 #else
-    unsigned short mode;
-    unsigned short __pad1;
-    unsigned short __seq;
-    unsigned short __pad2;
+  unsigned int mode;
+  unsigned short __seq;
+  unsigned short __pad2;
 #if defined(__x86_64__) && !defined(_LP64)
     u64 __unused1;
     u64 __unused2;
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<div class='path'>path: <a href='/guix/log/?id=3483e6444d541c8c157cb5af754d6af7faa4f845'>root</a>/<a href='/guix/log/po?id=3483e6444d541c8c157cb5af754d6af7faa4f845'>po</a>/<a href='/guix/log/po/doc?id=3483e6444d541c8c157cb5af754d6af7faa4f845'>doc</a>/<a href='/guix/log/po/doc/guix-manual.es.po?id=3483e6444d541c8c157cb5af754d6af7faa4f845'>guix-manual.es.po</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/po/doc/guix-manual.es.po?id=3483e6444d541c8c157cb5af754d6af7faa4f845&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2020-10-16 15:00:49 +0200'>2020-10-16</span></td><td><a href='/guix/commit/po/doc/guix-manual.es.po?id=4dd989708c7ab34df0b60ce9b6c0a8ca5c15e858'>nls: Update manual translations.</a></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2020-04-12 00:18:05 +0200'>2020-04-12</span></td><td><a href='/guix/commit/po/doc/guix-manual.es.po?id=935ef44b398353b5b6af94e185d7b0c3d833db0b'>nls: Update.</a></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2020-03-23 00:06:58 +0100'>2020-03-23</span></td><td><a href='/guix/commit/po/doc/guix-manual.es.po?id=86603d8660e42a3b5d8b407e456a98429943bc7e'>nls: Update.</a></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2020-02-14 09:01:29 +0000'>2020-02-14</span></td><td><a href='/guix/commit/po/doc/guix-manual.es.po?id=57718bdf6823aef291d114a457c42c984ac42791'>Revert "nls: Update 'es' translation of the manual."</a><span class='msg-avail'>...</span></td><td>Christopher Baines</td></tr>
<tr><td><span title='2020-02-14 04:45:53 +0100'>2020-02-14</span></td><td><a href='/guix/commit/po/doc/guix-manual.es.po?id=d156e3fbcd6fc61a39d1d32622b90b0f8f741729'>nls: Update 'es' translation of the manual.</a></td><td>Julien Lepiller</td></tr>
<tr><td><span title='2019-08-31 21:29:46 +0200'>2019-08-31</span></td><td><a href='/guix/commit/po/doc/guix-manual.es.po?id=b212fef4b076faccdd36335c728fd71321778716'>nls: Update 'es' translation of the manual.</a></td><td>Julien Lepiller</td></tr>
<tr><td><span title='2019-05-13 10:57:11 +0200'>2019-05-13</span></td><td><a href='/guix/commit/po/doc/guix-manual.es.po?id=8548cf6e95917f7b56042d2d275a08e91eedf31a'>nls: Update es translation.</a></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2019-05-01 11:33:32 +0200'>2019-05-01</span></td><td><a href='/guix/commit/po/doc/guix-manual.es.po?id=a3b32d57d6677fded92dbd3f4ecafbf9aceeb855'>nls: Fix cross-reference syntax error in 'guix-manual.es.po'.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2019-05-01 10:16:58 +0200'>2019-05-01</span></td><td><a href='/guix/commit/po/doc/guix-manual.es.po?id=d3619b296fd1db6441e09bb51b55a4264b9fd0ed'>nls: Update manual translations for de, es, fr, and zh_CN.</a></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2019-04-25 18:55:12 +0200'>2019-04-25</span></td><td><a href='/guix/commit/po/doc/guix-manual.es.po?id=57e2b24dc03e44e4e379436e63d29231f1f9d28c'>nls: Update 'es' translation.</a></td><td>Julien Lepiller</td></tr>
<tr><td><span title='2019-04-23 23:56:16 +0200'>2019-04-23</span></td><td><a href='/guix/commit/po/doc/guix-manual.es.po?id=6227e1b7477b71f31ea3bf8a74c32fe7238dcece'>doc: Add Spanish translation.</a><span class='msg-avail'>...</span></td><td>Miguel Ángel Arruga Vivas</td></tr>