tty: Remove lots of NULL checks

Many tty drivers contain 'can't happen' checks against NULL pointers passed
in by the tty layer. These have never been possible to occur. Even more
importantly if they ever do occur we want to know as it would be a serious
bug.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/char/n_r3964.c b/drivers/char/n_r3964.c
index ae377aa4..4a8215a 100644
--- a/drivers/char/n_r3964.c
+++ b/drivers/char/n_r3964.c
@@ -372,14 +372,8 @@
 static void put_char(struct r3964_info *pInfo, unsigned char ch)
 {
 	struct tty_struct *tty = pInfo->tty;
-
-	if (tty == NULL)
-		return;
-
 	/* FIXME: put_char should not be called from an IRQ */
-	if (tty->ops->put_char) {
-		tty->ops->put_char(tty, ch);
-	}
+	tty_put_char(tty, ch);
 	pInfo->bcc ^= ch;
 }