test-strftime: test for Solaris bug * modules/strftime-tests (Depends-on): Add strerror. * tests/test-strftime.c: Include <errno.h>. (posixtm_test): New function, containing the old 'main'. (struct tzalloc_test, struct localtime_rz_test): New types. (TZ, LT): New static vars. (tzalloc_test): New function. (main): Rewrite in terms of posixtm_test and tzalloc_test.