Revert "init.usb.rc: set sys.usb.config to none before changing it"

This can cause init to be stucked in a loop in very rare cases where
persist.sys.usb.config is set to "none" (because the "setprop
sys.usb.config none" action is added twice to the action list).
The original issue on encrypted devices has been fixed differently
by change # I350c5aab986f8ca86b95f316398d03012553e581

This reverts commit 80828af3de.

Change-Id: Id0a7af8dd861c8d10b80a13b540c8a339b432007

rootdir/init.usb.rc

@@ -88,5 +88,4 @@ on property:sys.usb.config=accessory,audio_source,adb
 # Used to set USB configuration at boot and to switch the configuration
 # when changing the default configuration
 on property:persist.sys.usb.config=*
-    setprop sys.usb.config none
     setprop sys.usb.config ${persist.sys.usb.config}