USB: gadget: drop irq-flags initialisations

There's no need to initialise irq-flags variables before saving the
interrupt state.

Drop the redundant initialisations from drivers that got this wrong.

Cc: Li Yang <leoyang.li@nxp.com>
Cc: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20210519093303.10789-4-johan@kernel.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>