staging: ks7010: factor out irq enable process to ks7010_sdio_init_irqs

This commit extracts sdio irq enable process to a new function
ks7010_sdio_init_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>