Allow dumping vibrator HAL.

Was missing permission to write to dumpstate's file, so this was failing
to dump.

Fixes: 145776393
Test: bugreport now shows:
-------------------------------------------------------------------------------
DUMP OF SERVICE android.hardware.vibrator.IVibrator/default:
HIDL:
...

Kernel:
...

(note, will fix 'HIDL' reference from AIDL HAL separately).

Change-Id: I5fbd55a4dbbd31a9c08260a247559e3dbd9a4046
diff --git a/public/hal_vibrator.te b/public/hal_vibrator.te
index 40d9c6b..a34621d 100644
--- a/public/hal_vibrator.te
+++ b/public/hal_vibrator.te
@@ -9,6 +9,8 @@
 
 allow hal_vibrator_client hal_vibrator_service:service_manager find;
 
+allow hal_vibrator_server dumpstate:fifo_file write;
+
 # vibrator sysfs rw access
 allow hal_vibrator sysfs_vibrator:file rw_file_perms;
 allow hal_vibrator sysfs_vibrator:dir search;