galaxys2: add opensource libril, remove ril class

- remove blob rild
- remove blob libril.so

Change-Id: I9f6d99bbd0ecf7c591c64a53e738339f0eaa3905

Conflicts:
	common.mk
galaxys2: libril: add a fallback to handle signalstrength for older modems

Change-Id: I66c253dbd8bf0db38b7e723cd43357752d2d9949
galaxys2: back to blob libril

opensource libril is causing memory problems

Change-Id: I3afc5430bcb52c4e31e2e79b1b2faf4bf53b4e3e