[ltp] X1 Carbon WWAN snafu

[Hans-Christian Hartmann]

Hi,

I have a 4gen X1 Carbon with the Sierra cellular modem (Sierra Wireless
EM7455 Qualcomm Snapdragon X7 LTE-A).  When I cold boot Linux (Mint
18.1) the mobile broadband is "unavailable".  When I cold boot Windows
10 and connect to internet.telekom, warm boot Linux, I can reconnect
just fine.

So the Windows driver puts the modem in the right mode (mood? :) and the
Linux Modem/NetworkManager combo forgets something important.

What can this be? How can I find out and fix this?

Thanx!
	Chris