[ALPS08668817] DISP: Fix MT6878 dual display cmdq timeout issue

Root Cause:
During CRTC3 state change to ENABLE and CRTC 3 enable,
the update_PQ for AOD configrue the CRTC3 PQ module.
Due to CRTC3 crtc enable not yet, bypass PQ cant wait frame done.

Add mtk_crtc->enabled judgement before PQ bypass flush.

MTK-Commit-Id: 383216fd7bc64fbbe9aee9ac73b570c971498d8a

Solution:
Signed-off-by: mtk12211 <shang.zhou@mediatek.com>
Change-Id: I72e3aea2a19e45734bc90db9e8b760a52032687c
CR-Id: ALPS08668817
Feature: display_mobile