This adds a netmon driver for ublox. The driver support both +COPS and
+CESQ commands to return the previously added ofono netmon types:
RSCP: Received Signal Code Power
ECN0: Received Energy Ratio
RSRQ: Reference Signal Received Quality
RSRP: Reference Signal Received Power
Current revision makes the driver use ref countig when chaining multiple
AT commands.
Adds U-Blox Toby L2 driver for setting the default APN via the
+UCGDFLT command. Currently only IPv4 is supported. APN is
not stored to modem's non-volatile memory. oFono will manage this
default APN via it's config storage.
When receiving an empty default APN, the value is reset.
For now the driver works only with bridged mode for 2G/3G.
Once it activates the context it reads the ip, netmask,
gw, dns and sets them in the context settings.
Djalal Harouni
Dragos Tatulea