usb: dwc3: gadget: don't request IRQs in atomic

commit b0d7ffd44ba9cd2dfbf299674418193a5f9ed21a upstream.

We cannot request an IRQ with spinlocks held
as that would trigger a sleeping inside
spinlock warning.

Reported-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>