drm/radeon: store the encoder in the radeon_crtc

This saves lots of lookups later.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/radeon/radeon_mode.h b/drivers/gpu/drm/radeon/radeon_mode.h
index 9f45e4b..2d78645 100644
--- a/drivers/gpu/drm/radeon/radeon_mode.h
+++ b/drivers/gpu/drm/radeon/radeon_mode.h
@@ -326,6 +326,7 @@
 	u32 pll_reference_div;
 	u32 pll_post_div;
 	u32 pll_flags;
+	struct drm_encoder *encoder;
 };
 
 struct radeon_encoder_primary_dac {