Huawei mode changing updated

[Aleksander Morgado]

> 
> One issue I had was:
> 
> [mm-at-serial-port.c:436] debug_log(): (ttyUSB2): --> 'AT^PREFMODE?<CR>'
> [mm-at-serial-port.c:436] debug_log(): (ttyUSB2): <-- '<CR><LF>^MODE:
> 0<CR><CR><LF><CR><CR><LF>^RSSILVL:0<CR><CR><LF><CR><CR><LF>^HRSSILVL:0<CR><LF>'
> [mm-at-serial-port.c:436] debug_log(): (ttyUSB2): <--
> '<CR><LF>^PREFMODE: 2<CR><LF><CR><LF>OK<CR><LF>'
> [mm-iface-modem.c:2416] after_set_load_current_modes_ready(): couldn't
> load current allowed/preferred modes: 'Unexpected PREFMODE response:
> '^RSSILVL:0
> 
> ^PREFMODE: 2''
> 
> for the EC168C, likely because the RSSILVL regex doesn't get enabled
> until the modem gets enabled, but you can still change allowed/preferred
> modes before that.  This isn't a blocker though, and can be fixed later.

That shouldn't happen, as all expected unsolicited messages are fully
disabled (as in, we detect them and ignore them) during setup_ports(),
which happens right before running the initialization sequence.

What I believe is happening is that the ^RSSILVL message comes with an
extra <CR> that the regex that we have in place doesn't expect; i.e. we
need "\\r+" instead of just "\\r". Could you confirm that?

-- 
Aleksander