Hide declaration of gets(3) for C11 and later.

gets(3) was removed from C11.

This reverts commit 1291680c2a0c23b2163198d27e00261ca206298b.

Bug: 14500800
Change-Id: I5e5146bdbb80f2be818a17f287b112bab37d1f6d
diff --git a/libc/include/stdio.h b/libc/include/stdio.h
index 62acb3a..e532de4 100644
--- a/libc/include/stdio.h
+++ b/libc/include/stdio.h
@@ -254,7 +254,9 @@
 int vdprintf(int, const char * __restrict, __va_list) __printflike(2, 0);
 
 #ifndef __AUDIT__
+#if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 201112L
 char* gets(char*) __warnattr("gets is very unsafe; consider using fgets");
+#endif
 int sprintf(char* __restrict, const char* __restrict, ...)
     __printflike(2, 3) __warnattr("sprintf is often misused; please use snprintf");
 char* tmpnam(char*) __warnattr("tmpnam possibly used unsafely; consider using mkstemp");