livepatch/s390: reorganize TIF thread flag bits

Group the TIF thread flag bits by their inclusion in the _TIF_WORK and
_TIF_TRACE macros.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>