MAINTAINERS: Add some more files to the HMP section

The hmp-commands-info.hx, hmp.h and include/monitor/hmp-target.h
files were classified as unmaintained. Let's add them to the
HMP section.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
diff --git a/MAINTAINERS b/MAINTAINERS
index adc5e4e..ba50167 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1183,8 +1183,9 @@
 M: Luiz Capitulino <lcapitulino@redhat.com>
 S: Maintained
 F: monitor.c
-F: hmp.c
-F: hmp-commands.hx
+F: hmp.[ch]
+F: hmp-commands*.hx
+F: include/monitor/hmp-target.h
 T: git git://repo.or.cz/qemu/qmp-unstable.git queue/qmp
 
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