MAINTAINERS: Add myself for files I touched recently

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1490014548-15083-6-git-send-email-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>

MAINTAINERS

@@ -1231,6 +1231,15 @@ M: Samuel Thibault <samuel.thibault@ens-lyon.org>
 S: Maintained
 F: backends/baum.c
 
+Command line option argument parsing
+M: Markus Armbruster <armbru@redhat.com>
+S: Supported
+F: include/qemu/option.h
+F: tests/test-keyval.c
+F: tests/test-qemu-opts.c
+F: util/keyval.c
+F: util/qemu-option.c
+
 Coverity model
 M: Markus Armbruster <armbru@redhat.com>
 S: Supported
@@ -1365,7 +1374,9 @@ X: include/qapi/qmp/
 F: include/qapi/qmp/dispatch.h
 F: tests/qapi-schema/
 F: tests/test-*-visitor.c
+F: tests/test-qapi-*.c
 F: tests/test-qmp-*.c
+F: tests/test-visitor-serialization.c
 F: scripts/qapi*
 F: docs/qapi*
 T: git git://repo.or.cz/qemu/armbru.git qapi-next