staging: comedi: adv_pci1710: remove 'has_irq' boardinfo

All the boards supported by this driver can use an interrupt. Remove
the unnecessary boardinfo.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>