rilmodem: probe availability of libandroid-properties

The Android telephony java framework is responsible for setting
several system properties. Since Android system properties are mostly
world-wide readable, they may mean something to other components such
as rild. In some cases, rild may not function normally without these
properties being set correctly.

A detail, but might not be complete, list of such properties is
available in
https://android.googlesource.com/platform/frameworks/base/+/master/telephony/java/com/android/internal/telephony/TelephonyProperties.java

Signed-off-by: You-Sheng Yang <vicamo@gmail.com>
rilmodem: setprop "gsm.version.baseband"

Signed-off-by: You-Sheng Yang <vicamo@gmail.com>
rilmodem: setprop "gsm.sim.state"

Signed-off-by: You-Sheng Yang <vicamo@gmail.com>
rilmodem: setprop "gsm.sim.operator.alpha"

Signed-off-by: You-Sheng Yang <vicamo@gmail.com>
rilmodem: setprop "gsm.sim.operator.numeric"

Signed-off-by: You-Sheng Yang <vicamo@gmail.com>
rilmodem: setprop "gsm.sim.operator.iso-country"

Signed-off-by: You-Sheng Yang <vicamo@gmail.com>
rilmodem: setprop "gsm.network.type"

Android defines all names for valid radio technologies in
android.telephony.ServiceState.rilRadioTechnologyToString(). Just
follow it.

Signed-off-by: You-Sheng Yang <vicamo@gmail.com>