drm/i915: Use compressed bpp when calculating m/n value for DP MST DSC

For obvious reasons, we use compressed bpp instead of pipe bpp for
DSC DP SST case. Lets be consistent and use compressed bpp instead of
pipe bpp, also in DP MST DSC case.

Signed-off-by: Stanislav Lisovskiy <[email protected]>
Reviewed-by: Vinod Govindapillai <[email protected]>
Fixes: d51f25e ("drm/i915: Add DSC support to MST path")
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]
(cherry picked from commit ea1deab)
Signed-off-by: Jani Nikula <[email protected]>

Author: StanFox1984

drivers/gpu/drm/i915/display/intel_dp_mst.c

@@ -232,7 +232,7 @@ static int intel_dp_dsc_mst_compute_link_config(struct intel_encoder *encoder,
 			return slots;
 	}
 
-	intel_link_compute_m_n(crtc_state->pipe_bpp,
+	intel_link_compute_m_n(crtc_state->dsc.compressed_bpp,
 			       crtc_state->lane_count,
 			       adjusted_mode->crtc_clock,
 			       crtc_state->port_clock,