drm/msm: Transition console to msm framebuffer

If booting a device using EFI, efifb will likely come up and claim the
console.  When the msm display stack finally comes up, we want the
console to move over to the msm fb, so add support to kick out any
firmware based framebuffers to accomplish the console transition.

Suggested-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Jeffrey Hugo <jeffrey.l.hugo@gmail.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Tested-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Rob Clark <robdclark@chromium.org>