drm/modes: Kill DRM_MODE_TYPE_CLOCK_CRTC_C define

No idea what the DRM_MODE_TYPE_CLOCK_CRTC_C define is supposed to
achieve. Totally unused so kill if off.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171114183258.16976-8-ville.syrjala@linux.intel.comReviewed-by: NAlex Deucher <alexander.deucher@amd.com>

include/drm/drm_modes.h

@@ -131,9 +131,6 @@ enum drm_mode_status {
 	MODE_ERROR = -1
 };
 
-#define DRM_MODE_TYPE_CLOCK_CRTC_C (DRM_MODE_TYPE_CLOCK_C | \
-				    DRM_MODE_TYPE_CRTC_C)
-
 #define DRM_MODE(nm, t, c, hd, hss, hse, ht, hsk, vd, vss, vse, vt, vs, f) \
 	.name = nm, .status = 0, .type = (t), .clock = (c), \
 	.hdisplay = (hd), .hsync_start = (hss), .hsync_end = (hse), \