tegra3-common: Add and use HTCTegra3RIL to fix parsing of operator infos

We have two ways to fix the mobile network scanning issue:
  1) We use the open source libril and set BOARD_USE_NEW_LIBRIL_HTC := true
  2) or we use the HTC libril with a custom HTCTegra3RIL class in the framework
     that correctly parses the QUERY_AVAILABLE_NETWORKS response.

This commit simply converts 1 to 2 because the HTC libril does some things we
want. For example it listens on the various rild sockets like rild-audio-gsm for
signals from libcall_volume or other services.

Change-Id: Ie363c60afe8860751684e3a053986c2a2837685e