1.support for multi-user access
2.support special cmd to control sensor
3.support userspace to set size of intermediate buffer
by ioctl: SNOIC_SET_BUFFER_SIZE
Change-Id: I9ce3a65b88b12c28388ec397431f1a277b120c2a
Signed-off-by: dongjiuzhu <dongjiuzhu1@xiaomi.com>