TTY: switch tty_insert_flip_char

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.

tty_insert_flip_char is the next one to proceed. This one is used all
over the code, so the patch is huge.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/hvc/hvc_console.c

@@ -672,7 +672,7 @@ int hvc_poll(struct hvc_struct *hp)
 				}
 			}
 #endif /* CONFIG_MAGIC_SYSRQ */
-			tty_insert_flip_char(tty, buf[i], 0);
+			tty_insert_flip_char(&hp->port, buf[i], 0);
 		}
 
 		read_total += n;