Display Workaround #0826 (SKL:ALL BXT:ALL) & #1059(CNL:A)
Hardware sometimes fails to wake memory from pkg C states fetching the
last few lines of planar YUV 420 (NV12) planes. This causes
intermittent underflow and corruption.
WA: Disable package C states or do not enable latency levels 1 through 7
(WM1 - WM7) on NV12 planes.

v2: Addressed review comments by Maarten.

v3: Adding reviewed by tag from Shashank Sharma

v4: Added reviewed by from Juha-Pekka Heikkila

v5: Rebased the series
Reviewed-by: NJuha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
Reviewed-by: NShashank Sharma <shashank.sharma@intel.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: NMahesh Kumar <mahesh1.kumar@intel.com>
Signed-off-by: NVidya Srinivas <vidya.srinivas@intel.com>
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1523245273-30264-9-git-send-email-vidya.srinivas@intel.com