drm/i915: TV mode_set sync up with 2D driver

Fix TV control save register for untouched bits, and color
knobs different definition for 945 and 965 chips.

Signed-off-by: Zhenyu Wang <zhenyu.z.wang@intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>

drivers/gpu/drm/i915/i915_reg.h

@@ -876,7 +876,7 @@
  */
 # define TV_ENC_C0_FIX			(1 << 10)
 /** Bits that must be preserved by software */
-# define TV_CTL_SAVE			((3 << 8) | (3 << 6))
+# define TV_CTL_SAVE			((1 << 11) | (3 << 9) | (7 << 6) | 0xf)
 # define TV_FUSE_STATE_MASK		(3 << 4)
 /** Read-only state that reports all features enabled */
 # define TV_FUSE_STATE_ENABLED		(0 << 4)