Hardcode depth to 32 bpp. It effectively was that way before because
that is the default surface depth, this just makes it explicit in the
code.
Rename depth to new_depth to make it consistent with the new_width +
new_height names. In theory we can make new_depth changeable (i.e.
allow the guest to fill in -- say -- 16 there). In practice the guests
don't try, the X-Server refuses to start if you ask it to use 16bpp
depth (via DefaultDepth in the Screen section).
Always return the correct rmask+gmask+bmask values for the given
new_depth.
Fix mode setting to also verify at new_depth to make sure we have a
correct DisplaySurface, even if the current video mode happes to be
16bpp (set by vgabios via bochs vbe interface). While being at it
switch over to use qemu_create_displaysurface_from, so the surface is
backed by guest-visible video memory and we save a memcpy.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
eb2f9b024d