[IrDA]: Delay needed when uploading firmware chunks

With 42101001.sb firmwares, we need a 10 ms delay between firmware chunks
upload on irda-usb.

Patch from Nigel Williams <nigelw@elder-gods.net>
Signed-off-by: Samuel Ortiz <samuel@sortiz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>