msm: mdss: enable under-run interrupt for secondary ctl

In split-display use-cases two ctl paths are active but one acts as
master and other as secondary. Currently under-run interrupt is only
enabled for master ctl. Enable under-run interrupt for secondary ctl
for seamless tracking.

Change-Id: I849419c4077fed384431079952027149c31b33fc
Signed-off-by: Ujwal Patel <ujwalp@codeaurora.org>
Signed-off-by: Jayant Shekhar <jshekhar@codeaurora.org>
Signed-off-by: Krishna Chaitanya Devarakonda <kdevarak@codeaurora.org>
Merge "msm: mdss: enable under-run interrupt for secondary ctl"
Merge 886f133dee08cf4e2855c149bebadc04a90ca5bd on remote branch

Change-Id: Ia4dc10b040de83db594809eca9f17977e3610953
Merge "Merge 886f133dee08cf4e2855c149bebadc04a90ca5bd on remote branch"