Staging: comedi: make comedi_free_board_minor local to comedi core

No one outside of the comedi core calls this function, so don't export
it to the world.

Cc: Ian Abbott <[e-mail]>
Cc: Frank Mori Hess <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/staging/comedi/comedi_fops.c

···
 		kfree(info);
 	}
 }
-EXPORT_SYMBOL_GPL(comedi_free_board_minor);
 
 int comedi_alloc_subdevice_minor(struct comedi_device *dev,
 				 struct comedi_subdevice *s)

drivers/staging/comedi/comedidev.h

···
 	return (void *)address;
 }
 
-void comedi_free_board_minor(unsigned minor);
 int comedi_alloc_subdevice_minor(struct comedi_device *dev,
 				 struct comedi_subdevice *s);
 void comedi_free_subdevice_minor(struct comedi_subdevice *s);

drivers/staging/comedi/internal.h

···
 
 int comedi_alloc_board_minor(struct device *hardware_device);
+void comedi_free_board_minor(unsigned minor);