Remove #if 0.

Signed-off-by: Bryan Bayerdorffer <bryanb@qti.qualcomm.com>

Author: bryanb-h2

libs/posix/pthread/rwlock/pthread_rwlock.ref.S

@@ -3,7 +3,6 @@
  * SPDX-License-Identifier: BSD-3-Clause-Clear
  */
 
-#if 0
 /* Almost done, try later */
 /*
  * pthread_tryrdlock(pthread_rwlock_t *lock)