TTY: switch tty_flip_buffer_push

Now, we start converting tty buffer functions to actually use
tty_port. This will allow us to get rid of the need of tty in many
call sites. Only tty_port will needed and hence no more
tty_port_tty_get in those paths.

Now, the one where most of tty_port_tty_get gets removed:
tty_flip_buffer_push.

IOW we also closed all the races in drivers not using tty_port_tty_get
at all yet.

Also we move tty_flip_buffer_push declaration from include/linux/tty.h
to include/linux/tty_flip.h to all others while we are changing it
anyway.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/s390/char/sclp_tty.c b/drivers/s390/char/sclp_tty.c
index 19b7c51..14b4cb8 100644
--- a/drivers/s390/char/sclp_tty.c
+++ b/drivers/s390/char/sclp_tty.c
@@ -343,7 +343,7 @@
 		break;
 	case CTRLCHAR_CTRL:
 		tty_insert_flip_char(&sclp_port, cchar, TTY_NORMAL);
-		tty_flip_buffer_push(tty);
+		tty_flip_buffer_push(&sclp_port);
 		break;
 	case CTRLCHAR_NONE:
 		/* send (normal) input to line discipline */
@@ -355,7 +355,7 @@
 			tty_insert_flip_char(&sclp_port, '\n', TTY_NORMAL);
 		} else
 			tty_insert_flip_string(&sclp_port, buf, count - 2);
-		tty_flip_buffer_push(tty);
+		tty_flip_buffer_push(&sclp_port);
 		break;
 	}
 	tty_kref_put(tty);