HSI: nokia-modem: Add cmt-speech support

Register cmt-speech driver in nokia-modem driver and forward
hsi channel information.

Acked-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Tested-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Sebastian Reichel <sre@kernel.org>