Fix memory leaks.
Found by Coverity.
* gettext-runtime/intl/loadmsgcat.c (_nl_load_domain): Free allocated memory
before returning in out-of-memory case.
* gettext-runtime/intl/localealias.c (relocate2): Define fallback.
(read_alias_file): Invoke relocate2 instead of relocate. Free the allocated
memory.
