usbcam: Added support for USB camera

Added support to Libxcam for USB cameras. Verified
with 1080p Logitech C920 camera and test-device-manager
app.

Test command line:
test-device-manager -f YUYV -m dma -d video -p --usb /dev/videoX
test-device-manager -m mmap -s -f BA10 -d still --usb /dev/videoX -i 1

Signed-off-by: Sameer Kibey <sameer.kibey@intel.com>
4 files changed