zephyr-kernel: Drop the Arduino USB CDC patch

This patch is not applying to the new Zephyr version provided by
meta-zephyr. Also, the implementation needs changes based on discussions
with the Zephyr community. We will be reimplementing it as part of:

https://booting.oniroproject.org/distro/meta-zephyr/-/issues/16



In the meanwhile, drop this patch to avoid build issues.

Signed-off-by: Andrei Gherzan <andrei.gherzan@huawei.com>