drm/i915/skl+: Remove data_rate from watermark struct, v2.

It's only used in one function, and can be calculated without caching it
in the global struct by using drm_atomic_crtc_state_for_each_plane_state.

There are loops over all planes, including planes that don't exist.
This is harmless, because data_rate will always be 0 for them and we
never program them when updating watermarks.

Changes since v1:
- Rename rate back to data_rate, and change array name to
  plane_data_rate. (Matt)
- Remove whitespace. (Paulo)

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1477489299-25777-5-git-send-email-maarten.lankhorst@linux.intel.com
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>

drivers/gpu/drm/i915/intel_drv.h

@@ -501,10 +501,6 @@ struct intel_crtc_wm_state {
 			struct skl_pipe_wm optimal;
 			struct skl_ddb_entry ddb;
 
-			/* cached plane data rate */
-			unsigned plane_data_rate[I915_MAX_PLANES];
-			unsigned plane_y_data_rate[I915_MAX_PLANES];
-
 			/* minimum block allocation */
 			uint16_t minimum_blocks[I915_MAX_PLANES];
 			uint16_t minimum_y_blocks[I915_MAX_PLANES];