nptl: fix gcc noreturn warning
Current builds show the warning:
CC libpthread/nptl/sysdeps/unix/sysv/linux/mq_notify.os
libpthread/nptl/sysdeps/unix/sysv/linux/mq_notify.c: In function 'helper_thread':
libpthread/nptl/sysdeps/unix/sysv/linux/mq_notify.c:142:3: warning:
function declared 'noreturn' has a 'return' statement [enabled by default]
Looking at glibc, it does not mark this function as noreturn. Testing
code size, gcc is smart enough to detect the while(1){} never actually
returns regardless of the attribute. So drop it to keep in sync with
glibc and to avoid the warning.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>