We can shrink size of "struct inet_bind_bucket" by 50%, using read_pnet() and write_pnet()

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
---
 include/net/inet_hashtables.h   |    7 +++++++
 net/ipv4/inet_connection_sock.c |    4 ++--
 net/ipv4/inet_hashtables.c      |    6 +++---
 3 files changed, 12 insertions(+), 5 deletions(-)