staging: comedi: use unsigned samples for comedi_buf_put()/get()

Sample values in comedi are generally represented as unsigned values.
`comedi_buf_put()` and `comedi_buf_get()` use a `short` to hold the
16-bit data value being transferred to or from the comedi buffer.
Change them to use `unsigned short` for consistency.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/staging/comedi/comedidev.h b/drivers/staging/comedi/comedidev.h
index 9a854b1..143be80 100644
--- a/drivers/staging/comedi/comedidev.h
+++ b/drivers/staging/comedi/comedidev.h
@@ -346,8 +346,8 @@
 unsigned int comedi_buf_read_alloc(struct comedi_async *, unsigned int);
 unsigned int comedi_buf_read_free(struct comedi_async *, unsigned int);
 
-int comedi_buf_put(struct comedi_async *, short);
-int comedi_buf_get(struct comedi_async *, short *);
+int comedi_buf_put(struct comedi_async *, unsigned short);
+int comedi_buf_get(struct comedi_async *, unsigned short *);
 
 void comedi_buf_memcpy_to(struct comedi_async *async, unsigned int offset,
 			  const void *source, unsigned int num_bytes);