drm/msm/sde: move frame_done_timeout after phys encoder disable

During virtual encoder disable, frame_done_timeout is checked
incorrectly before disabling master phys encoder. The frame
transfer wait is accounted only in the phys encoder disable which
would eventually lead to resetting the frame_done_timeout. Move
the check after master phys encoder disable to avoid the error.

Change-Id: Iab4e180091f53c64f5b2ff9ac1843cb584bc5f76
Signed-off-by: Veera Sundaram Sankaran <veeras@codeaurora.org>