drm/msm/sde: fix the missing ROT_90 true inline rotation flag

Add the missing, ROT_90 true inline rotation flag to
the src_flags in sde_plane. The missing flag leads to
image corruption during inline rotation.

Change-Id: I28bd57855607f4676391a177ac43db3207455ff0
Signed-off-by: Veera Sundaram Sankaran <veeras@codeaurora.org>