Rework the radio vs rild property split.
Only label properties with the ril. prefix with rild_prop.
Allow rild and system (and radio) to set radio_prop.
Only rild can set rild_prop presently.
diff --git a/system.te b/system.te
index 58e4f47..6466e96 100644
--- a/system.te
+++ b/system.te
@@ -148,6 +148,7 @@
 
 # Property Service write
 allow system system_prop:property_service set;
+allow system radio_prop:property_service set;
 
 # ctl interface
 allow system ctl_default_prop:property_service set;