staging: dgnc: dgnc_tty: Do not use 0 for NULL pointer

Do not use 0 for NULL pointer.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Lidza Louina <lidza.louina@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/dgnc/dgnc_tty.c

@@ -520,7 +520,7 @@ void dgnc_sniff_nowait_nolock(struct channel_t *ch, uchar *text, uchar *buf, int
 		/*
 		 *  Loop while data remains.
 		 */
-		while (nbuf > 0 && ch->ch_sniff_buf != 0) {
+		while (nbuf > 0 && ch->ch_sniff_buf) {
 			/*
 			 *  Determine the amount of available space left in the
 			 *  buffer.  If there's none, wait until some appears.