uml: remove a useless function

arch/um/drivers/chan_kern.c::chan_out_fd() is not used by anyone.  Remove it.
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: WANG Cong <wangcong@zeuux.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/um/drivers/chan_kern.c

@@ -583,19 +583,6 @@ int parse_chan_pair(char *str, struct line *line, int device,
 	return 0;
 }
 
-int chan_out_fd(struct list_head *chans)
-{
-	struct list_head *ele;
-	struct chan *chan;
-
-	list_for_each(ele, chans) {
-		chan = list_entry(ele, struct chan, list);
-		if (chan->primary && chan->output)
-			return chan->fd;
-	}
-	return -1;
-}
-
 void chan_interrupt(struct list_head *chans, struct delayed_work *task,
 		    struct tty_struct *tty, int irq)
 {

arch/um/include/chan_kern.h

@@ -44,7 +44,6 @@ extern void close_chan(struct list_head *chans, int delay_free_irq);
 extern int chan_window_size(struct list_head *chans, 
 			     unsigned short *rows_out, 
 			     unsigned short *cols_out);
-extern int chan_out_fd(struct list_head *chans);
 extern int chan_config_string(struct list_head *chans, char *str, int size,
 			      char **error_out);