drm: Add bus flag for Sharp-specific signals

Add the DRM_BUS_FLAG_SHARP_SIGNALS to the drm_bus_flags enum.

This flags can be used when the display must be driven with the
Sharp-specific signals SPL, CLS, REV, PS.
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190603153120.23947-2-paul@crapouillou.net

include/drm/drm_connector.h

@@ -323,6 +323,8 @@ enum drm_panel_orientation {
  *					edge of the pixel clock
  * @DRM_BUS_FLAG_SYNC_SAMPLE_NEGEDGE:	Sync signals are sampled on the falling
  *					edge of the pixel clock
+ * @DRM_BUS_FLAG_SHARP_SIGNALS:		Set if the Sharp-specific signals
+ *					(SPL, CLS, PS, REV) must be used
  */
 enum drm_bus_flags {
 	DRM_BUS_FLAG_DE_LOW = BIT(0),
@@ -341,6 +343,7 @@ enum drm_bus_flags {
 	DRM_BUS_FLAG_SYNC_DRIVE_NEGEDGE = DRM_BUS_FLAG_SYNC_NEGEDGE,
 	DRM_BUS_FLAG_SYNC_SAMPLE_POSEDGE = DRM_BUS_FLAG_SYNC_NEGEDGE,
 	DRM_BUS_FLAG_SYNC_SAMPLE_NEGEDGE = DRM_BUS_FLAG_SYNC_POSEDGE,
+	DRM_BUS_FLAG_SHARP_SIGNALS = BIT(8),
 };
 
 /**