msm: mdss: Unlock correct mutex in AD setup

The incorrect mutex for the BL file descriptor was being unlocked
in AD setup. Removed the incorrect unlock and replaced it with an
unlock on the correct mutex.

Change-Id: I276823c34d1183b69d7af06bae8b02cb7e1b56b1
Signed-off-by: Benet Clark <benetc@codeaurora.org>
Signed-off-by: Carl Vanderlip <carlv@codeaurora.org>
msm: mdss: Balance clock requests in histogram enable

Balance the clock requests in histogram enable to prevent clocks from being
left on.

Change-Id: I45fc029049b68cceb56d0dc40f7819aca0625a58
Signed-off-by: Carl Vanderlip <carlv@codeaurora.org>