Allow system to dump sensor hal process

Test: tested taking bugreport, sensor HAL traces show up in
      "VM TRACES JUST NOW"
Test: tested trigger ANR by `adb shell am hang --allow-restart`,
      sensor HAL traces shows up in /data/anr/traces.txt
Bug: 63096400
Change-Id: I1d012b9d9810f987be7aaf9d68abfd9c3184ac5c

private/system_server.te

@@ -245,6 +245,7 @@ allow system_server {
   hal_bluetooth_server
   hal_camera_server
   hal_graphics_composer_server
+  hal_sensors_server
   hal_vr_server
   mediacodec # TODO(b/36375899): hal_omx_server
 }:process { signal };

public/dumpstate.te

@@ -70,6 +70,7 @@ allow dumpstate {
   hal_bluetooth_server
   hal_camera_server
   hal_graphics_composer_server
+  hal_sensors_server
   hal_vr_server
   mediacodec # TODO(b/36375899): hal_omx_server
 }:process signal;