usb: modify the permission of USB gadget hal

Currently, USB gadgdet hal couldn't access configfs nodes during
device booting. The permission of configfs nodes are root as default,
and they are modified to system by init process. Therefore, USB
gadget HAL can't access them before permission changes completely.

The patch will modify permission of USB gadget hal so that it can
access configfs nodes without permission change.

Bug: 204378488
Test: check connection time
Change-Id: I97f5446a51183225227744043e4a6e0088fecf0b

conf/init.gs201.usb.rc

@@ -67,7 +67,8 @@ on early-boot
     # etr_miu function
     mkdir /config/usb_gadget/g1/functions/etr_miu.gs11
 
-    setprop vendor.usb.functions.ready 1
+    # disable permission change. TODO (b/206902205): add back later
+    # setprop vendor.usb.functions.ready 1
 
 on boot
     write /config/usb_gadget/g1/bcdDevice 0x0510

usb/android.hardware.usb@1.3-service.gs201.rc

@@ -1,7 +1,8 @@
+# TODO (b/206902205): remove root permission later
 service vendor.usb-hal-1-3 /vendor/bin/hw/android.hardware.usb@1.3-service.gs201
     class hal
-    user system
-    group system shell mtp
+    user root
+    group root system shell mtp
 
 on post-fs
     chown root system /sys/class/typec/port0/power_role