[PATCH] net: kmemcheck annotation in struct socket

struct socket has a 16 bit hole that triggers kmemcheck warnings.

As suggested by Ingo, use kmemcheck annotations

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: David S. Miller <davem@davemloft.net>