usb: dwc2: gadget: Fix GOUTNAK flow for Slave mode.

usb: dwc2: gadget: Fix GOUTNAK flow for Slave mode.

Because of dwc2_hsotg_ep_stop_xfr() function uses poll
mode, first need to mask GINTSTS_GOUTNAKEFF interrupt.
In Slave mode GINTSTS_GOUTNAKEFF interrupt will be
aserted only after pop OUT NAK status packet from RxFIFO.

In dwc2_hsotg_ep_sethalt() function before setting
DCTL_SGOUTNAK need to unmask GOUTNAKEFF interrupt.

Tested by USBCV CH9 and MSC tests set in Slave, BDMA and DDMA.
All tests are passed.

Fixes: a4f827714539a ("usb: dwc2: gadget: Disable enabled HW endpoint in dwc2_hsotg_ep_disable")
Fixes: 6070636c4918c ("usb: dwc2: Fix Stalling a Non-Isochronous OUT EP")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
Link: https://lore.kernel.org/r/e17fad802bbcaf879e1ed6745030993abb93baf8.1626152924.git.Minas.Harutyunyan@synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>