msm: camera: crm: Unlink devices before clearing the link

There can be a potential deadlock - unlink waits on context
lock, context waits to finish config_dev, config_dev is waiting
for link lock to add request. By calling unlink outside the
lock will resolve this deadlock. It also solves the problem of
workq being freed before unlink in case there is no lock for
unlink.

Change-Id: Ia4e911fd32c6b32b368acf620b5ccbb84dd0cb85
Signed-off-by: Harsh Shah <harshs@codeaurora.org>
Signed-off-by: Karthik Anantha Ram <kartanan@codeaurora.org>