staging: comedi: ni_660x: support NI PXI-6624

Florent Boudet reports success using a NI PXI-6624 board with a
trivially modified version of the "ni_660x" driver (addition to the PCI
device ID table and comedi board table).  He did this with the
out-of-tree Comedi drivers at www.comedi.org, but it applies equally to
the in-tree "staging" drivers.

He reports the PXI-6624 is basically the same as the PXI-6602, but with
isolated channels and external voltage source.

Add support for NI PXI-6224 to the "ni_660x" driver.

(Maybe the driver should be renamed to "ni_66xx"?)

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Cc: Florent Boudet <flboudet@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/staging/comedi/Kconfig b/drivers/staging/comedi/Kconfig
index 109168c..7841399 100644
--- a/drivers/staging/comedi/Kconfig
+++ b/drivers/staging/comedi/Kconfig
@@ -993,7 +993,7 @@
 	select COMEDI_NI_TIOCMD
 	---help---
 	  Enable support for National Instruments PCI-6601 (ni_660x), PCI-6602,
-	  PXI-6602 and PXI-6608.
+	  PXI-6602, PXI-6608 and PXI-6624.
 
 	  To compile this driver as a module, choose M here: the module will be
 	  called ni_660x.