disp: msm: dsi: remove early return from dma_cmd_wait_for_done

In ASYNC wait mode, next command kickoff can happen before previous
command ISR execution is completed in below sequence:

ASYNC command A -> triggered

dsi_ctrl_isr for command A -> fired and executed
	atomic_set(&dsi_ctrl->dma_irq_trig, 1);

wait_for_done for command A -> returns early as
	dsi_ctrl->dma_irq_trig is 1

ASYNC Command B -> triggered

wait_for_done for command B -> waiting for cmd_dma_done

dsi_ctrl_isr for command A -> executes
	complete_all(&dsi_ctrl->irq_info.cmd_dma_done);

wait_for_done for command B -> returns success incorrectly based on
	complete_all of previous command isr and disable_status_interrupt()
	is not called.

This leads to refcount of dma_done going wrong and dsi_ctrl_isr is not
enabled on suspend resume.

To fix this issue, mark command transfer successful only based on
complete_all(cmd_dma_done). This way disable_status_interrupt() will be
always called either from dsi_ctrl_isr or wait_for_done().

Change-Id: I0379ea7ff82a1e077b95f6996d11d1722de00936
Signed-off-by: Ritesh Kumar <riteshk@codeaurora.org>