[media] uvcvideo: Hardcode the index/selector relationship for XU controls

[media] uvcvideo: Hardcode the index/selector relationship for XU controls

Devices advertise XU controls using a bitmask, in which each bit
corresponds to a control. The control selector, used to query the
control, isn't available in the USB descriptors.

All known UVC devices use control selectors equal to the control bit
index plus one. Hardcode that relationship in the driver, making the
UVCIOC_CTRL_ADD ioctl obsolete. All necessary information about XU
controls can be obtained by the driver at enumeration time.

The UVCIOC_CTRL_ADD ioctl is still supported for compatibility reasons,
but now always returns -EEXIST.

Finally, control mappings are now on a per-device basis and no longer
global.

As this changes the userspace interface, bump the driver version number
to 1.0.0 (it was about time).

Signed-off-by: Martin Rubli <martin_rubli@logitech.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>