TTY: move ldisc data from tty_struct: read_* and echo_* and canon_* stuff

All the ring-buffers...
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

include/linux/tty.h

@@ -272,16 +272,6 @@ struct tty_struct {
 	 */
 	unsigned char closing:1;
 	unsigned short minimum_to_wake;
-	char *read_buf;
-	int read_head;
-	int read_tail;
-	int read_cnt;
-	unsigned char *echo_buf;
-	unsigned int echo_pos;
-	unsigned int echo_cnt;
-	int canon_data;
-	unsigned long canon_head;
-	unsigned int canon_column;
 	struct mutex atomic_read_lock;
 	struct mutex atomic_write_lock;
 	struct mutex output_lock;