staging: comedi: comedi_fops: make internal function static

The function do_become_nonbusy() is only referenced in this file.
Make it static.

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