msm: camera: Avoid calling unmap hardware virtual address

Avoid calling unmap hardware virtual address if the buffer is
not accessed by hardware. MAP and UNMAP both needs to be protected
by shared access and hardware access flags. Release buffers
failure observed in userspace on trying to unmap buffers that are
not allocated with hardware access

Change-Id: I26f9f85f8beb57f8a57ec90443771f20cdb5cbdd
Signed-off-by: Krishnankutty Kolathappilly <kkolatha@codeaurora.org>
Signed-off-by: Soundrapandian Jeyaprakash <jsoundra@codeaurora.org>