staging: rtl8723au: usb_dvobj_init(): A NULL pointer check for usb_host_endpoints makes no sense

struct usb_host_interface points to an array of
struct usb_host_endpoints - it makes no sense to do a NULL pointer
check for each pointer.

Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>