kmod: patch: cleanup error paths

Right now, if there is a failure in patch_make_dynrelas_list(),
patch_free_objects() is called twice; once in the error section of
patch_make_dynrelas_list() and again in the err_objects section of
patch_init().

This fixes this and cleans up the error handling a bit.

Signed-off-by: Seth Jennings <sjenning@redhat.com>