staging: ks7010: factor out irq setup process to ks7010_sdio_setup_irqs

This commit extract sdio irq setup process into a new
function ks7010_sdio_setup_irqs to improve readability.

Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>