hw/m68k: add Nubus macfb video card

This patch adds support for a graphic framebuffer device.
This device can be added as a sysbus device or as a NuBus device.

It is accessed as a framebuffer but the color palette can be set.

Co-developed-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Hervé Poussineau <hpoussin@reactos.org>
Reviewed-by: Thomas Huth <huth@tuxfamily.org>
Message-Id: <20191026164546.30020-9-laurent@vivier.eu>
diff --git a/MAINTAINERS b/MAINTAINERS
index 7892ab5..bd0df67 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -922,8 +922,10 @@
 S: Maintained
 F: hw/misc/mac_via.c
 F: hw/nubus/*
+F: hw/display/macfb.c
 F: include/hw/misc/mac_via.h
 F: include/hw/nubus/*
+F: include/hw/display/macfb.h
 
 MicroBlaze Machines
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