This clashes with a static gettid in test source
gdb compile failed, gdb.threads/clone-new-thread-event.c:46:1: error: \
static declaration of 'gettid' follows non-static declaration
46 | gettid (void)
In file included from /usr/include/unistd.h:1170,
/usr/include/bits/unistd_ext.h:34:16: note: previous declaration of 'gettid' \
34 | extern __pid_t gettid (void) __THROW;
Fix this by renaming the static gettid to local_gettid.
Tested on x86_64-linux.
Committed to trunk.
[gdb/testsuite] Fix clone-new-thread-event.c with glibc 2.30