msm: mdss: handle ESD status for split DSI panels with broadcast mode

For split DSI panels when broadcast mode is enabled, the ESD status
check command needs to be sent to both the controllers at the same
time. Also, the status needs to be checked from the buffer of the
trigger controller. Add change to take care of this.

Change-Id: I47c8cacd657a4528d1859a34ba1d588a54357bb9
Signed-off-by: Padmanabhan Komanduru <pkomandu@codeaurora.org>