Revert "init_jflte: remove ro.telephony.default_cdma_sub from r970s"

This reverts commit 10863b6fc6d3d45a2cbcfc3503a25f758edb701c.

Change-Id: Ia1f70bbe9af888a384f5fc284cf26b61ccfb0893
jf: Remove modem links scripts

 * Create the symlinks ourselves at build time. Remounting the system
   partition to do this is just stupid.

Change-Id: I224c20af820554661fe027e5835b18cb5589c694