comedi: Move "comedi_isadma.h" to <linux/comedi/comedi_isadma.h>

comedi: Move "comedi_isadma.h" to <linux/comedi/comedi_isadma.h>

Some of the header files in "drivers/comedi/drivers/" are common enough
to be useful to out-of-tree comedi driver modules.  Using them for
out-of-tree module builds is hampered by the headers being outside the
"include/" directory so it is desirable to move them.

There are about a half a dozen or so Comedi device drivers that use the
"comedi_isadma" module to add ISA DMA support.  The macros and
declarations to use that module are in the "comedi_isadma.h" header file
in the comedi "drivers" directory.  Move it into
"include/linux/comedi/".

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://lore.kernel.org/r/20211117120604.117740-6-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>