drm/msm/sde: cache crtc during encoder enable state

Commit 1a9ba3e79a3e ("drm/msm/sde: move crtc caching
to encoder_modeset") started caching the crtc in modeset
state instead of encoder enable. An encoder enable
call might happen without modeset. Allow caching
crtc information for those cases.

Change-Id: I2589180a7a6583541f545194d3146a9dcffdbce7
Signed-off-by: Dhaval Patel <pdhaval@codeaurora.org>