USB: serial: option: add support for Telit LE910 PID 0x1206

This patch adds support for 0x1206 PID of Telit LE910.

Since the interfaces positions are the same than the ones for
0x1043 PID of Telit LE922, telit_le922_blacklist_usbcfg3 is used.

Signed-off-by: Daniele Palmas <dnlplm@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>