staging: comedi: comedidev.h: introduce some 'range_is_external' helpers
staging: comedi: comedidev.h: introduce some 'range_is_external' helpers

The comedi_krange includes a flags member that currently identifies the
'units' of the range (RF_UNIT) and if the range is from an internal or
external source (RF_EXTERNAL).

Introduce some helper functions to check if a given range is from an
external source.

Signed-off-by: H Hartley Sweeten <382ff55d8e07d1082d179e669636cd1552da4f36@visionengravers.com>
Reviewed-by: Ian Abbott <9e6ba6483b6a3e14d61f7c987e72ecb5b46122d6@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <4645f7897fd33786a2ee1264d590b3c400559d85@linuxfoundation.org>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs