regex: port __libc_lock_define usage to C89 * lib/regex_internal.h (__libc_lock_define) [!_LIBC]: Remove. (struct re_dfa_t): Use #ifdef instead. '__libc_lock_define (, lock)' does not conform to C89, as it has an empty macro argument. Reported by Aharon Robbins in <http://sourceware.org/ml/libc-alpha/2012-12/msg00456.html>.