Make regex safe for g++. This fixes one real bug (an "err"

Make regex safe for g++.  This fixes one real bug (an "err"
that should have been "*err").
* config/srclist.txt: Add glibc bug 1241.
* lib/regex_internal.h (re_calloc): New macro, consistent with
re_malloc etc.  All callers of calloc changed to use re_calloc.
* lib/regex_internal.c (build_wcs_upper_buffer): Return reg_errcode_t,
not int.  All callers changed.
* lib/regcomp.c (re_compile_fastmap_iter): Don't use alloca
(mb_cur_max); just use an array of size MB_LEN_MAX.
* lib/regexec.c (push_fail_stack): Use re_realloc, not realloc.
(find_recover_state): Change "err" to "*err"; this fixes what
appears to be a real bug.
(check_arrival_expand_ecl_sub): Be consistent about reg_errcode_t
versus int.