drm: Pass 'flags' from the caller to .get_scanout_position()

Preparation for moving the early vblank IRQ logic into
radeon_get_crtc_scanoutpos().

v2: Fix radeon_drv.c compile warning (Mario)

Reviewed-by: mario.kleiner.de@gmail.com
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

drivers/gpu/drm/radeon/radeon_mode.h

@@ -800,6 +800,7 @@ extern int radeon_crtc_cursor_move(struct drm_crtc *crtc,
 				   int x, int y);
 
 extern int radeon_get_crtc_scanoutpos(struct drm_device *dev, int crtc,
+				      unsigned int flags,
 				      int *vpos, int *hpos, ktime_t *stime,
 				      ktime_t *etime);