drm: Remove now pointelss blob->data casts

Now that blob->data is void* again we don't need the casts anymore.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180223192506.29992-2-ville.syrjala@linux.intel.com
Reviewed-by: Shashank Sharma <shashank.sharma@intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index 035784d..0646b10 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -1351,7 +1351,7 @@ static struct drm_property_blob *setcmap_new_gamma_lut(struct drm_crtc *crtc,
 	if (IS_ERR(gamma_lut))
 		return gamma_lut;
 
-	lut = (struct drm_color_lut *)gamma_lut->data;
+	lut = gamma_lut->data;
 	if (cmap->start || cmap->len != size) {
 		u16 *r = crtc->gamma_store;
 		u16 *g = r + crtc->gamma_size;