Add capability for sensor hal to use wakelock

Bug: 63995095
Test: no more wake lock acquire failures in QCOM and nanohub sensor
      hal
Change-Id: I2a5c2e29ecb66869a408f53998b6074ed07b493a
diff --git a/sensors/1.0/default/android.hardware.sensors@1.0-service.rc b/sensors/1.0/default/android.hardware.sensors@1.0-service.rc
index 059e5db..6e78082 100644
--- a/sensors/1.0/default/android.hardware.sensors@1.0-service.rc
+++ b/sensors/1.0/default/android.hardware.sensors@1.0-service.rc
@@ -1,5 +1,5 @@
 service sensors-hal-1-0 /vendor/bin/hw/android.hardware.sensors@1.0-service
     class hal
     user system
-    group system
-    capabilities SYS_NICE
+    group system wakelock
+    capabilities BLOCK_SUSPEND SYS_NICE