disp: msm: sde: decouple FETCH_PIPE_ACTIVE logic from setup_blendstages

Setup blendstages is done per LM but FETCH_PIPE_ACTIVE is per CTL.
Overloading mixer blendstage setup with fetch pipe logic can lead
to HW programming errors. Refactor the logic for setting
FETCH_PIPE_ACTIVE by adding a new op that allows caller to provide
a bitmask of all pipes required to be active on this CTL. This new
logic includes support for:
 - 4LM use-cases, staging pipes for all LMs within a CRTC
 - Demura fetch-pipe without need for tracking via active_cfg (removed)

Also, lower the cyclomatic complexity in setup_blendstages by moving
the logic for obtaining the mixer config settings in to a helper
function.

Change-Id: I2907b359ffad5734be5b06f44919b5ddb1ef3f7c
Signed-off-by: Steve Cohen <cohens@codeaurora.org>

msm/sde/sde_crtc.h

@@ -225,7 +225,6 @@ struct sde_crtc_misr_info {
  * @property_defaults : Array of default values for generic property support
  * @output_fence  : output release fence context
  * @stage_cfg     : H/w mixer stage configuration
- * @active_cfg    : H/w pipes active that shouldn't be staged
  * @debugfs_root  : Parent of debugfs node
  * @priv_handle   : Pointer to external private handle, if present
  * @vblank_cb_count : count of vblank callback since last reset
@@ -298,7 +297,6 @@ struct sde_crtc {
 	struct sde_fence_context *output_fence;
 
 	struct sde_hw_stage_cfg stage_cfg;
-	struct sde_hw_stage_cfg active_cfg;
 	struct dentry *debugfs_root;
 	void *priv_handle;