drm: Constify TV mode names

Make the mode names passed to drm_mode_create_tv_properties() const.

 drivers/gpu/drm/i2c/ch7006.ko:
-.rodata                       596
+.rodata                       664
-.data                        7064
+.data                        6992

 drivers/gpu/drm/nouveau/nouveau.ko:
-.rodata                      146808
+.rodata                      146904
-.data                        178624
+.data                        178528

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_tv.c b/drivers/gpu/drm/i915/intel_tv.c
index 0568ae6..590ceab 100644
--- a/drivers/gpu/drm/i915/intel_tv.c
+++ b/drivers/gpu/drm/i915/intel_tv.c
@@ -1579,7 +1579,7 @@
 	struct intel_encoder *intel_encoder;
 	struct intel_connector *intel_connector;
 	u32 tv_dac_on, tv_dac_off, save_tv_dac;
-	char *tv_format_names[ARRAY_SIZE(tv_modes)];
+	const char *tv_format_names[ARRAY_SIZE(tv_modes)];
 	int i, initial_mode = 0;
 
 	if ((I915_READ(TV_CTL) & TV_FUSE_STATE_MASK) == TV_FUSE_STATE_DISABLED)
@@ -1677,7 +1677,7 @@
 
 	/* Create TV properties then attach current values */
 	for (i = 0; i < ARRAY_SIZE(tv_modes); i++)
-		tv_format_names[i] = (char *)tv_modes[i].name;
+		tv_format_names[i] = tv_modes[i].name;
 	drm_mode_create_tv_properties(dev,
 				      ARRAY_SIZE(tv_modes),
 				      tv_format_names);