Fix some incompatibilities with gcc -ansi -pedantic. * lib/regex.h (__restrict_arr): Don't use the [restrict] syntax if compiling pedantically with GCC, unless it's C99 or later. Don't trust sys/cdefs.h's definition of __restrict_arr, either, as it mishandles gcc -ansi -pedantic as well. * lib/regex_internal.h (re_token_t): Don't use enum bitfields if gcc -pedantic. * lib/regexec.c (check_node_accept_bytes): Don't use auto initializers for struct if -pedantic, unless it's C99 or later.