TTY: convert more flipping functions

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

Now 4 string flipping ones are on turn:
* tty_insert_flip_string_flags
* tty_insert_flip_string_fixed_flag
* tty_prepare_flip_string
* tty_prepare_flip_string_flags

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/isicom.c b/drivers/tty/isicom.c
index 3205b2e..e9fc15f 100644
--- a/drivers/tty/isicom.c
+++ b/drivers/tty/isicom.c
@@ -650,8 +650,8 @@
 			break;
 		}
 	} else {				/* Data   Packet */
-
-		count = tty_prepare_flip_string(tty, &rp, byte_count & ~1);
+		count = tty_prepare_flip_string(&port->port, &rp,
+				byte_count & ~1);
 		pr_debug("%s: Can rx %d of %d bytes.\n",
 			 __func__, count, byte_count);
 		word_count = count >> 1;