livepatch: add arch-specific headers to MAINTAINERS

Add arch-specific livepatch.h for s390 and powerpc to MAINTAINERS
F: patterns.
Reported-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

MAINTAINERS

@@ -9854,6 +9854,8 @@ S:	Maintained
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching.git
 F:	Documentation/ABI/testing/sysfs-kernel-livepatch
 F:	Documentation/livepatch/
+F:	arch/powerpc/include/asm/livepatch.h
+F:	arch/s390/include/asm/livepatch.h
 F:	arch/x86/include/asm/livepatch.h
 F:	include/linux/livepatch.h
 F:	kernel/livepatch/