Fix support for CDMA devices in SamsungRIL.

These fixes are ported from jt1134's fascinatemtd patches and CM7.  For
CM9, the fixes are applied to SamsungRIL directly instead of elsewhere in
the telephony framework.  They include:

- Signal strength reporting: pass raw integer values.
- Voice registration: convert base station values from hex to dec.
- Data call setup/deactivate: start/stop pppd_cdma service and pull network
  parameters from pppd ip-up script.
- CDMA subscription: add missing PRL version from system properties.

Changes from CM7:

Note use of "ril.cdma.data_state" property instead of
"ril.cdma.data_ready".  This property has three states:

- Disconnect(ed): ril.cdma.data_state=0: stop pppd_cdma service.
- Connecting:     ril.cdma.data_state=1: (re)start pppd_cdma.
- Connected:      ril.cdma.data_state=2: pppd_cdma has responded.

The disconnect (0) and connecting (1) states are set by SamsungRIL on the
deactivation and setup, respectively, of a data call.  Prior to setting the
connecting (1) state, SamsungRIL sets the "net.cdma.datalinkinterface" for
pppd_runner's use.

After setting to the connecting (1) state, SamsungRIL waits for pppd_cdma
to respond by (itself) setting the connected (2) state.  This should be
done at the end of a /system/etc/ppp/ip-up script, after that script sets
the following interface values, which SamsungRIL uses to complete the data
call state:

- net.cdma.ppp.interface: $IFNAME (typically "ppp0")
- net.$IFNAME.local-ip:   pppd's local IPv4 address
- net.$IFNAME.remote-ip:  pppd's remote IPv4 address
- net.$IFNAME.dns1:       pppd's primary DNS address
- net.$IFNAME.dns2:       pppd's secondary DNS address