drm/msm/dpu: drop EAGAIN check from dpu_format_populate_layout

The pipe's layout is not cached, corresponding data structure is zeroed
out each time in the dpu_plane_sspp_atomic_update(), right before the
call to _dpu_plane_set_scanout() -> dpu_format_populate_layout().

Drop plane_addr comparison against previous layout and corresponding
EAGAIN handling.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>