Fix a regression in glibc 2.27 when built without ldconfig.  See
<https://sourceware.org/bugzilla/show_bug.cgi?id=22977> for details.

diff --git a/include/libc-symbols.h b/include/libc-symbols.h
index 6137304b0b..7d630f36d8 100644
--- a/include/libc-symbols.h
+++ b/include/libc-symbols.h
@@ -508,7 +508,7 @@ for linking")
 # ifndef __ASSEMBLER__
 #  if !defined SHARED && IS_IN (libc) && !defined LIBC_NONSHARED \
       && (!defined PIC || !defined NO_HIDDEN_EXTERN_FUNC_IN_PIE) \
-      && !defined NO_HIDDEN
+      && !defined NO_HIDDEN && defined USE_LDCONFIG
 #   define __hidden_proto_hiddenattr(attrs...) \
   __attribute__ ((visibility ("hidden"), ##attrs))
 #   define hidden_proto(name, attrs...) \
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