Enable the media / V4L2 / uvcvideo kernel stack so a USB camera exposes
/dev/videoN for majestic's usbcam second-camera path.
To fit the 8M NOR (2M kernel / 5M rootfs) without dropping any sensor
library, uvcvideo and the videobuf2 framework are built INTO the kernel
(=y) instead of shipped as rootfs modules: the kernel partition had ~55 KB
of spare room while the rootfs was tight, so ~44 KB of weight moves from
rootfs to kernel. Resulting images: uImage 2022.8 KB / 2048 KB (25 KB
spare), rootfs squashfs 5080 KB / 5120 KB (40 KB spare).
GSPCA -- a separate driver for non-UVC webcams, pulled in by "default m
depends on VIDEO_V4L2" -- is disabled.
No kernel patch is carried: mmap capture works on stock uvcvideo once
majestic aligns its mmap() prototype with this MMAP_MUSL build's
uint32_t-offset shim (a userspace fix), so the earlier read()/fileio
uvcvideo patch is not needed.
Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>
