[TCP]: Delete unused header file net/ipv4/tcp_yeah.h.

Delete the apparently unused header file net/ipv4/tcp_yeah.h.
Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/tcp_yeah.h

-#include <linux/mm.h>
-#include <linux/module.h>
-#include <linux/skbuff.h>
-#include <linux/inet_diag.h>
-#include <asm/div64.h>
-
-#include <net/tcp.h>