staging: comedi: ii_pci20kc: this is an ISA board not a PCI board

The Intelligent Instrumentation PCI-20001C board is a legacy PC/XT/AT
8-bit ISA board not a PCI board.  The "PCI" appears to mean "Personal
Computer Instrumentation".

Move the Kconfig option into the COMEDI_ISA group.

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