Telephony: set default language of Canada as 'en'

The Canada SIM cards have the dual-IMSI functionality for the roaming
service. If it is working and the default system language is not set,
the system language can be changed by the MCC of the 2nd IMSI. So, the
default language should not be 'null'. This patch fills in the default
language of Canada as English.

Bug: 11361337
Change-Id: Iea6213e3ceca4a1cf054ebd9a13bb1d5574013b1