Fix glob memory leak in GSS initialization

In loadConfigFiles, call globfree even if glob fails, since glob can
allocate memory and report partial results on failure.  Also
initialize globbuf before calling glob; this is not strictly required,
but hedges against hypothetical libc implementation bugs which could
leave globbuf.gl_pathc or globbuf.gl_pathv uninitialized on error.

ticket: 7981