usb: renesas_usbhs: fixup interrupt status clear method

When interrupt happened, renesas_usbhs driver gets irq status
by usbhs_status_get_each_irq(), and cleared all status by using 0.
But, this method is incorrect,
since extra interrupt might occur between them.
This patch cleared corresponding bits only

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>