Make HDMI_CEC a vendorPriviliged permission

Vendors implement the CEC HAL and put it in
the vendor partition. For the CEC driver to run it
needs android.permission.HDMI_CEC

See goto/systemsdk-design

Change-Id: I88738d08292c450ed6821106e3844feab0b3bcfe
Test: m -j; flashall elfin
diff --git a/core/res/AndroidManifest.xml b/core/res/AndroidManifest.xml
index 6df7fcb..8292c46 100644
--- a/core/res/AndroidManifest.xml
+++ b/core/res/AndroidManifest.xml
@@ -1315,7 +1315,7 @@
          This should only be used by HDMI-CEC service.
     -->
     <permission android:name="android.permission.HDMI_CEC"
-        android:protectionLevel="signature|privileged" />
+        android:protectionLevel="signature|privileged|vendorPrivileged" />
 
     <!-- @SystemApi Allows an application to use location features in hardware,
          such as the geofencing api.