drm/i915/skl+: pass skl_wm_level struct to wm compute func

drm/i915/skl+: pass skl_wm_level struct to wm compute func

This patch passes skl_wm_level structure itself to watermark
computation function skl_compute_plane_wm function (instead
of its internal parameters). It reduces number of arguments
required to be passed.

v2: Addressed review comments by Shashank Sharma

v3: Adding reviewed by tag from Shashank Sharma

v4: Added reviewed by from Juha-Pekka Heikkila

v5: Rebased the series

Reviewed-by: Juha-Pekka Heikkila <[email protected]>
Reviewed-by: Shashank Sharma <[email protected]>
Signed-off-by: Mahesh Kumar <[email protected]>
Signed-off-by: Vidya Srinivas <[email protected]>
Reviewed-by: Maarten Lankhorst <[email protected]>
Signed-off-by: Maarten Lankhorst <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]