gutils: Fix minor memory leak on error path
gutils: Fix minor memory leak on error path

Introduced in commit d011223085063ff23589fb92c7e68bcfb50fdd02.

Coverity CID: 1382472

Signed-off-by: Philip Withnall <29c2a2ac2a854b9cf047275aa9de346d096be2e0@endlessm.com>

endlessm/glib,endlessm/glib,endlessm/glib,endlessm/glib,johne53/MB3Glib,endlessm/glib,johne53/MB3Glib,johne53/MB3Glib,johne53/MB3Glib,johne53/MB3Glib,johne53/MB3Glib