MAINTAINERS: Add a missing entry for the Old World machines

Signed-off-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: NDavid Gibson <david@gibson.dropbear.id.au>
Reviewed-by: NMark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Message-Id: <20181125205000.10324-9-philmd@redhat.com>
Signed-off-by: NLaurent Vivier <laurent@vivier.eu>

MAINTAINERS

@@ -967,6 +967,7 @@ F: hw/ppc/mac_oldworld.c
 F: hw/pci-host/grackle.c
 F: hw/misc/macio/
 F: hw/intc/heathrow_pic.c
+F: include/hw/intc/heathrow_pic.h
 
 PReP
 M: Hervé Poussineau <hpoussin@reactos.org>