drm/msm/dsi-staging: serialize DSI ESD trigger commands

Esd trigger command from adb need to be ignored if already
another esd recovery process is in progress.

Change-Id: I69cd4c0d59c4197d6dfbfc1198feedbfe66e3cc0
Signed-off-by: Raviteja Tamatam <travitej@codeaurora.org>