usb: chipidea: udc: move _ep_queue into an unlocked function

There is no need to call ep_queue unlocked inside the own driver. We
move its functionionality into an unlocked version.

This patch removes potential unlocked timeslots inside
isr_setup_status_phase and isr_get_status_response, in which the lock
got released just before acquired again inside usb_ep_queue.

Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Reviewed-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>