staging: comedi: fix checkpatch error
staging: comedi: fix checkpatch error

Fixed an error found by checkpatch.pl.
ERROR: space required after that ',' (ctx:VxV)
./drivers/ni_mio_common.c:3764

Signed-off-by: Geliang Tang <d12999005f6151b9468b6f2bd6d86bf9f7b59e02@163.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