xlat: workaround V4L2_CID_USER_IMX_BASE Linux kernel ABI breakage

Linux kernel commit v4.18-rc2-106-g421860b9d47053badce4b247576fa48df9ab4c48
has changed the value of V4L2_CID_USER_IMX_BASE constant introduced
by commit v4.13-rc1~141^2~121 because the old value was already used
by V4L2_CID_USER_MAX217X_BASE.

This is of course an ABI breakage that affects Linux kernels starting
with 4.13 and up to 4.18, as well as their LTS derivatives.

Since the imx driver didn't provide any public control ID definitions,
it looks like the best way to handle this situation is to pretend that
the old value of V4L2_CID_USER_IMX_BASE didn't exist.

* xlat/v4l2_control_id_bases.in (V4L2_CID_USER_IMX_BASE): Redefine.

Co-Authored-by: Eugene Syromyatnikov <evgsyr@gmail.com>
(cherry picked from commit 0d4eb1af)