s390 tty: Prepare for put_char to return success/fail

Put the changes into the drivers first.  This will still compile/work but
produce a warning if bisected so can still be debugged

Signed-off-by: Alan Cox <alan@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/s390/char/sclp_tty.c b/drivers/s390/char/sclp_tty.c
index e3b3d39..40b1152 100644
--- a/drivers/s390/char/sclp_tty.c
+++ b/drivers/s390/char/sclp_tty.c
@@ -412,14 +412,14 @@
  * - including previous characters from sclp_tty_put_char() and strings from
  * sclp_write() without final '\n' - will be written.
  */
-static void
+static int
 sclp_tty_put_char(struct tty_struct *tty, unsigned char ch)
 {
 	sclp_tty_chars[sclp_tty_chars_count++] = ch;
 	if (ch == '\n' || sclp_tty_chars_count >= SCLP_TTY_BUF_SIZE) {
 		sclp_tty_write_string(sclp_tty_chars, sclp_tty_chars_count);
 		sclp_tty_chars_count = 0;
-	}
+	} return 1;
 }
 
 /*