drm/i915: Fix VLV CRC reading.

Adding missing Display mmio reg offset.

Credits-to: Laws, Philip <philip.laws@intel.com>
Cc: He, Shuang <shuang.he@intel.com>
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_reg.h

@@ -2627,7 +2627,7 @@ enum punit_power_well {
 
 #define PORT_DFT_I9XX				0x61150
 #define   DC_BALANCE_RESET			(1 << 25)
-#define PORT_DFT2_G4X				0x61154
+#define PORT_DFT2_G4X		(dev_priv->info.display_mmio_offset + 0x61154)
 #define   DC_BALANCE_RESET_VLV			(1 << 31)
 #define   PIPE_SCRAMBLE_RESET_MASK		(0x3 << 0)
 #define   PIPE_B_SCRAMBLE_RESET			(1 << 1)