MAINTAINERS: adjust to livepatch .klp.arch removal

Commit 1d05334d ("livepatch: Remove .klp.arch") removed
arch/x86/kernel/livepatch.c, but missed to adjust the LIVE PATCHING entry
in MAINTAINERS.

Since then, ./scripts/get_maintainer.pl --self-test=patterns complains:

  warning: no file matches  F:  arch/x86/kernel/livepatch.c

So, drop that obsolete file entry in MAINTAINERS.

Fixes: 1d05334d ("livepatch: Remove .klp.arch")
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

MAINTAINERS

@@ -9855,7 +9855,6 @@ T:	git git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching.g
 F:	Documentation/ABI/testing/sysfs-kernel-livepatch
 F:	Documentation/livepatch/
 F:	arch/x86/include/asm/livepatch.h
-F:	arch/x86/kernel/livepatch.c
 F:	include/linux/livepatch.h
 F:	kernel/livepatch/
 F:	samples/livepatch/