vexpress: Add camera HAL

Add Linaro's generic camera HAL to vexpress builds and tidyup
handling of /dev/video* entries.

This does not complete enablement of camera on vexpress: the kernel
config needs USB Video Class enabling and even with this video
capture fails with EPIPE.

Change-Id: If1fb6b73d9fcb06b15fa8844691a1c0ef959ebe3
Signed-off-by: Jon Medhurst <tixy@linaro.org>
3 files changed