vga-pci: add qext region to mmio

Add a qemu extented register range to the standard vga mmio bar.
Right nowe there are two registers:  One readonly register returning the
size of the region (so we can easily add more registers there if needed)
and one endian control register, so guests (especially ppc) can flip
the framebuffer endianness as they need it.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
hw/display/vga: Remove unused arrays dmask4 and dmask16

Following cleanup of the vga device code in commit d2e043a8041,
the arrays dmask4 and dmask16 are now unused. gcc doesn't warn
about this, but clang does; remove them.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Merge remote-tracking branch 'remotes/kraxel/tags/pull-vga-20141015-1' into staging

vga-pci: add qext region to mmio
vga: Remove unused arrays dmask4 and dmask16

# gpg: Signature made Wed 15 Oct 2014 10:12:06 BST using RSA key ID D3E87138
# gpg: Good signature from "Gerd Hoffmann (work) <kraxel@redhat.com>"
# gpg:                 aka "Gerd Hoffmann <gerd@kraxel.org>"
# gpg:                 aka "Gerd Hoffmann (private) <kraxel@gmail.com>"

* remotes/kraxel/tags/pull-vga-20141015-1:
  hw/display/vga: Remove unused arrays dmask4 and dmask16
  vga-pci: add qext region to mmio

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>