drm/msm/dpu: move pipe_hw to dpu_plane_state

In preparation to adding fully virtualized planes, move struct
dpu_hw_sspp instance from struct dpu_plane to struct dpu_plane_state, as
it will become a part of state (variable, changes during runtime) rather
than part of a plane (ideally should be statically allocated during boot).

The sspp pointer is set at the dpu_plane_reset(), since this is the
function which allocates the state. Once we have fully virtual
plane<->SSPP relationship, the SSPP will be allocated dynamically in the
dpu_plane_atomic_check() function.
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Tested-by: Abhinav Kumar <quic_abhinavk@quicinc.com> # sc7280
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/527322/
Link: https://lore.kernel.org/r/20230316161653.4106395-6-dmitry.baryshkov@linaro.orgSigned-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

drivers/gpu/drm/msm/disp/dpu1/dpu_plane.h

@@ -18,6 +18,7 @@
  * struct dpu_plane_state: Define dpu extension of drm plane state object
  * @base:	base drm plane state object
  * @aspace:	pointer to address space for input/output buffers
+ * @hw_sspp:	pointer to corresponding SSPP instance
  * @stage:	assigned by crtc blender
  * @needs_qos_remap: qos remap settings need to be updated
  * @multirect_index: index of the rectangle of SSPP
@@ -31,6 +32,7 @@
 struct dpu_plane_state {
 	struct drm_plane_state base;
 	struct msm_gem_address_space *aspace;
+	struct dpu_hw_sspp *hw_sspp;
 	enum dpu_stage stage;
 	bool needs_qos_remap;
 	uint32_t multirect_index;