drm: msm: Fix blue screen glitch problem on DSI

DSI display will have a short blue screen flicker
issue when enabling early splash. This is caused by
the DSI state setting. The patch is to fix this.

CRs-Fixed: 2225630
Change-Id: I69f1d9473827ff5d420f9581e709f37d00b2c2e8
Signed-off-by: Guchun Chen <guchunc@codeaurora.org>
Signed-off-by: Camus Wong <camusw@codeaurora.org>