Remove use of deprecated ustat interface in glibc 2.28:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85835

Taken from upstream:

https://gcc.gnu.org/viewcvs/gcc?view=revision&revision=260684

diff --git a/libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.cc b/libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.cc
index 858bb2184505..de18e56d11cf 100644
--- a/libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.cc
+++ b/libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.cc
@@ -157,7 +157,6 @@ typedef struct user_fpregs elf_fpregset_t;
 # include <sys/procfs.h>
 #endif
 #include <sys/user.h>
-#include <sys/ustat.h>
 #include <linux/cyclades.h>
 #include <linux/if_eql.h>
 #include <linux/if_plip.h>
@@ -250,7 +249,19 @@ namespace __sanitizer {
 #endif // SANITIZER_LINUX || SANITIZER_FREEBSD
 
 #if SANITIZER_LINUX && !SANITIZER_ANDROID
-  unsigned struct_ustat_sz = sizeof(struct ustat);
+  // Use pre-computed size of struct ustat to avoid <sys/ustat.h> which
+  // has been removed from glibc 2.28.
+#if defined(__aarch64__) || defined(__s3</td></tr></table>
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