USB: serial: option: add support for Quectel UC20

commit c0992d0f upstream.

Add support for Quectel UC20 and blacklist the QMI interface.

Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
[johan: amend commit message ]
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>