musb_host: streamline musb_cleanup_urb() calls

The argument for the 'is_in' parameter of musb_cleanup_urb()
is always extracted from an URB that's passed to the function.
So that parameter is superfluous; remove it.

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>