usb: dwc2: gadget: Fix ISOC transfer complete handling for DDMA

usb: dwc2: gadget: Fix ISOC transfer complete handling for DDMA

When last descriptor in a descriptor list completed with XferComplete
interrupt, core switching to handle next descriptor and assert BNA
interrupt. Both these interrupts are set while dwc2_hsotg_epint()
handler called. Each interrupt should be handled separately: first
XferComplete interrupt then BNA interrupt, otherwise last completed
transfer will not be giveback to function driver as completed
request.

Fixes: 6fd90cfd9c4d ("usb: dwc2: Change ISOC DDMA flow")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
Link: https://lore.kernel.org/r/a36981accc26cd674c5d8f8da6164344b94ec1fe.1631386531.git.Minas.Harutyunyan@synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>