drm/msm/sde: fix reading of the pingpong counters

Correct register enum and masks used for reading out the
pingpong vsync and line count values.

Change-Id: Iaa2a1034d38ad9f741c5201de2de7c5f39aeaaf5
Signed-off-by: Lloyd Atkinson <latkinso@codeaurora.org>
2 files changed