bullhead/apns: Remove dun type for Canada operators

Radio Button Option is enabled for the pre-programmed APNs
for Tethering Profile in Canada operators. However, Tethering
doesn't use these APNs. Thus, it can caused confusion to user.

Tether apns are used in frameworks/base/core/res/res/values-mcc302-mncXXX.

Bug: 24570140
Change-Id: I94ef3f209d52fe07b5aa5b65e1b852be34a2678b
1 file changed