drm: BIT(DRM_ROTATE_?) -> DRM_ROTATE_?

Only property creation uses the rotation as an index, so convert the
to figure the index when needed.

v2: Use the new defines to build the _MASK defines (Sean)

Cc: intel-gfx@lists.freedesktop.org
Cc: linux-arm-msm@vger.kernel.org
Cc: freedreno@lists.freedesktop.org
Cc: malidp@foss.arm.com
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Liviu Dudau <Liviu.Dudau@arm.com>
Cc: Sean Paul <seanpaul@chromium.org>
Acked-by: Liviu Dudau <Liviu.Dudau@arm.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> (v1)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: http://patchwork.freedesktop.org/patch/msgid/1469771405-17653-1-git-send-email-joonas.lahtinen@linux.intel.com

drivers/gpu/drm/i915/intel_fbc.c

@@ -775,7 +775,7 @@ static bool intel_fbc_can_activate(struct intel_crtc *crtc)
 		return false;
 	}
 	if (INTEL_INFO(dev_priv)->gen <= 4 && !IS_G4X(dev_priv) &&
-	    cache->plane.rotation != BIT(DRM_ROTATE_0)) {
+	    cache->plane.rotation != DRM_ROTATE_0) {
 		fbc->no_fbc_reason = "rotation unsupported";
 		return false;
 	}