Add 'vendor.' prefix to a vendor HAL service name

To prevent property name collisions between properties of system and
vendor, 'vendor.' prefix must be added to a vendor HAL service name.
You can see the details in http://go/treble-sysprop-compatibility.

Test: succeeded building and tested on a walleye device
Bug: 36796459
Change-Id: I4e8fbee791ec917a8f627a1366f4d44ec7e6febc
diff --git a/drm/1.0/default/android.hardware.drm@1.0-service.rc b/drm/1.0/default/android.hardware.drm@1.0-service.rc
index e7beca3..a3457b5 100644
--- a/drm/1.0/default/android.hardware.drm@1.0-service.rc
+++ b/drm/1.0/default/android.hardware.drm@1.0-service.rc
@@ -1,4 +1,4 @@
-service drm-hal-1-0 /vendor/bin/hw/android.hardware.drm@1.0-service
+service vendor.drm-hal-1-0 /vendor/bin/hw/android.hardware.drm@1.0-service
     class hal
     user media
     group mediadrm drmrpc