msm: camera: Remove unused code used to map userspace buffers.

Remove MSM_CAM_IOCTL_SET_MEM_MAP_INFO IOCTL support, since the
usage of this IOCTL is now depreciated.

Change-Id: I8d0c99874ae9bd87aaaa10e039f2511a6dd20775
Signed-off-by: Kiran Kumar H N <hurlisal@codeaurora.org>