msm: camera: Fix couple of potential race conditions.

When the camera daemon dies(either killed manually or
some crash), all the open fds(server node, mctl pp node,
config node) will be closed. However the order in which
these are closed is not predictable. Hence there might
be a couple of potential race conditions triggering
kernel panics. Fix those potential race conditions.

Change-Id: I2ceb608ba99cbc698832a8dcf1ddfcaa7a0a0675
Signed-off-by: Kiran Kumar H N <hurlisal@codeaurora.org>