bochs: add support for native graphics

Per our discussions with Gerd, qemu will now always do native graphics
on coreboot. The VGA BIOS capability is not needed and will no longer
be supported. Attempts to build without native graphics will result in
an error.

This code builds for both x86 emulation targets. I'm hitting an issue
testing that is unrelated to coreboot; if someone can test, that
would be helpful. Be sure to start qemu with -vga std.

We also add a test for the PCI BAR being zero and return silently if it
is.

Change-Id: I66188f61e1bac7ad93c989cc10f3e0b55140e148
Signed-off-by: Ronald G. Minnich <rminnich@google.com>
Reviewed-on: http://review.coreboot.org/4258
Tested-by: build bot (Jenkins)
Reviewed-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
3 files changed