Fix wrong voice mail ringtone for secondary SIM.

Reproduce steps:
1. Android One with Dual SIM.
2. Set different ringtone for both voice mail.
3. SIM2 receives a voice mail but ring tone is SIM1's.

The ring tone URI for voice mail is from default phone object,
change phone object to the right one.

Change-Id: I497b681a697456c84aea5f71b68419b3c4afac2d
1 file changed