HTCQualcommRIL: fix data drops when switching state

* HTC RIL always throws this exception after the initial data call
  setup, so only switch ifname if the call goes from active to inactive.
* Prevents data drop due to empty address/DNS/gateway when radio tech
  switches to/from LTE/3G/2G.

Change-Id: I29107f549029d467ed01c0eba46561d65ca4d5d7
Merge branch 'cm-10.1' into martincz