drm/gma500: Make all chips use gma_wait_for_vblank

Also remove the duplicated oaktrail function.

Signed-off-by: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>

diff --cc drivers/gpu/drm/gma500/cdv_intel_dp.c
Simple merge

diff --cc drivers/gpu/drm/gma500/mdfld_intel_display.c
Simple merge

diff --cc drivers/gpu/drm/gma500/oaktrail_crtc.c
Simple merge

diff --cc drivers/gpu/drm/gma500/oaktrail_hdmi.c
Simple merge

diff --cc drivers/gpu/drm/gma500/psb_intel_display.c
Simple merge

diff --cc drivers/gpu/drm/gma500/psb_intel_drv.h
Simple merge

diff --cc drivers/gpu/drm/gma500/psb_intel_sdvo.c
Simple merge