V4L/DVB (10639): gspca - sq905: New subdriver.

Add initial support for cameras based on the SQ Technologies SQ-905
chipset (USB ID 2770:9120) to V4L2 using the gspca infrastructure.
Currently only supports one resolution and doesn't attempt to inform
libv4l what image flipping options are needed.

Signed-off-by: Adam Baker <linux@baker-net.org.uk>
Signed-off-by: Theodore Kilgore <kilgota@auburn.edu>
Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>