MAINTAINERS: Update QAPI stanza for commit fb0bc835

Commit fb0bc835 moved code from scripts/qapi-*.py to
scripts/qapi/*.py.  It neglected to update MAINTAINERS: scripts/qapi*
matches only the former, not the latter.  Do that now.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Message-Id: <20180620124827.17106-1-armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

MAINTAINERS

@@ -1623,7 +1623,8 @@ 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: scripts/qapi-gen.py
+F: scripts/qapi/*
 F: docs/devel/qapi*
 T: git git://repo.or.cz/qemu/armbru.git qapi-next