Fix global typo in last change: use chmod u-w, not chmod u-x.

Fix global typo in last change: use chmod u-w, not chmod u-x.
Spotted by Paul Eggert and Bruce Korb.
* modules/alloca-opt, modules/argz, modules/arpa_inet:
* modules/byteswap, modules/configmake, modules/fcntl:
* modules/fnmatch, modules/getopt, modules/glob, modules/inttypes:
* modules/localcharset, modules/netinet_in, modules/poll:
* modules/stdbool, modules/stdint, modules/sys_select:
* modules/sys_socket, modules/sys_stat, modules/sysexits: