ueventd.rc: Give the USB group read/write access to the MTP USB driver.

Change-Id: I305671848dbdf427333dc088f83f88cea1b33945
Signed-off-by: Mike Lockwood <lockwood@android.com>
diff --git a/rootdir/ueventd.rc b/rootdir/ueventd.rc
index 265a65a..05118bc 100644
--- a/rootdir/ueventd.rc
+++ b/rootdir/ueventd.rc
@@ -69,6 +69,7 @@
 /dev/qmi1                 0640   radio      radio
 /dev/qmi2                 0640   radio      radio
 /dev/bus/usb/*            0660   root       usb
+/dev/mtp_usb              0660   root       usb
 
 # CDMA radio interface MUX
 /dev/ts0710mux*           0640   radio      radio