Add SELinux config for new SensorFusion property

Add required SELinux configuration to support the sensor
configuration property:
sensors.aosp_low_power_sensor_fusion.maximum_rate

Test: use getprop to verify presence and readability
of the new property. dumpsys sensorservice to verify
sensor service is picking up the property value.

Change-Id: I96b8fd6ce72d7a5bf69b028802b329b03f261585
diff --git a/private/property_contexts b/private/property_contexts
index d556acf..2dfc092 100644
--- a/private/property_contexts
+++ b/private/property_contexts
@@ -1566,3 +1566,6 @@
 # Properties for Quick Start setup.
 ro.quick_start.oem_id u:object_r:quick_start_prop:s0 exact string
 ro.quick_start.device_id u:object_r:quick_start_prop:s0 exact string
+
+# Properties for sensor service
+sensors.aosp_low_power_sensor_fusion.maximum_rate u:object_r:sensors_config_prop:s0 exact uint