xt_qtaguid: Fix kmemleak error in TIME_WAIT sockets

This reverts commit 4335ab13 ("xt_qtaguid: check xt_sock
socket before releasing"). This commit causes kmemleak errors
with the following trace -

unreferenced object (size 184):
  comm "softirq", pid 0, jiffies 14724 (age 4906.640s)
  hex dump (first 32 bytes):
    3d 6e f5 25 0a be 6e 8a c9 d8 bb c2 00 50 72 cb  =n.%..n......Pr.
    02 00 06 80 00 00 00 00 00 00 00 00 58 8a 42 c5  ............X.B.
  backtrace:
    inet_twsk_alloc+0x40/0x1e8
    tcp_time_wait+0x48/0x1fc
    tcp_rcv_state_process+0xa74/0xc10
    tcp_v4_do_rcv+0x2c8/0x338
    tcp_v4_rcv+0x4f8/0x8fc
    ip_local_deliver_finish+0x130/0x2c0
    ip_rcv_finish+0x2d0/0x348
    __netif_receive_skb_core+0x710/0x7c4
    netif_receive_skb_internal+0x60/0xac
    __rmnet_deliver_skb+0x1ec/0x3f8
    __netif_receive_skb_core+0x588/0x7c4
    process_backlog+0x90/0x14c
    net_rx_action+0xb4/0x234
    __do_softirq+0x14c/0x370
    irq_exit+0x84/0xe0
    handle_IPI+0x120/0x354

This is because xt_qtaguid holds on to references incorrectly and
never releases the slab cache even after the time wait socket
timer expiry.

inet_twsk_alloc TCP created tw atomic_read(&tw->tw_refcnt) 0, called
from tcp_time_wait+0x48/0x1fc
inet_twsk_alloc tw tw->tw_daddr 61.110.245.37 tw->tw_rcv_saddr
10.190.110.138 tw->tw_sport 29387 tw->tw_dport 20480
tcp_time_wait tw atomic_read(&tw->tw_refcnt) 3, called from
tcp_rcv_state_process+0xa74/0xc10
tcp_time_wait inet_twsk_schedule tw atomic_read (&tw->tw_refcnt) 4,
called from tcp_rcv_state_process+0xa74/0xc10
inet_twsk_put tw atomic_read(&tw->tw_refcnt) 4, called from
tcp_time_wait+0x1b0/0x1fc
xt_socket: xt_socket_get4_sk tw atomic_read(&tw->tw_refcnt) 4, called
from qtaguid_mt+0x568/0x8bc
xt_socket: xt_socket_get4_sk tw if (sk) atomic_read (&tw->tw_refcnt)
5, called from qtaguid_mt+0x568/0x8bc
xt_socket: xt_socket_get4_sk tw atomic_read(&tw->tw_refcnt) 5, called
from qtaguid_mt+0x568/0x8bc
xt_socket: xt_socket_get4_sk tw if (sk) atomic_read (&tw->tw_refcnt)
6, called from qtaguid_mt+0x568/0x8bc
xt_socket: xt_socket_get4_sk tw atomic_read(&tw->tw_refcnt) 6, called
from qtaguid_mt+0x568/0x8bc
xt_socket: xt_socket_get4_sk tw if (sk) atomic_read (&tw->tw_refcnt)
7, called from qtaguid_mt+0x568/0x8bc
xt_socket: xt_socket_get4_sk tw atomic_read(&tw->tw_refcnt) 7, called
from qtaguid_mt+0x568/0x8bc
xt_socket: xt_socket_get4_sk tw if (sk) atomic_read (&tw->tw_refcnt)
8, called from qtaguid_mt+0x568/0x8bc
xt_socket: xt_socket_get4_sk tw atomic_read(&tw->tw_refcnt) 8, called
from qtaguid_mt+0x568/0x8bc
xt_socket: xt_socket_get4_sk tw if (sk) atomic_read (&tw->tw_refcnt)
9, called from qtaguid_mt+0x568/0x8bc
inet_twsk_put tw atomic_read(&tw->tw_refcnt) 9, called from
tcp_v4_rcv+0x8e0/0x8fc
tw_timer_handler tw atomic_read(&tw->tw_refcnt) 8, called from
call_timer_fn+0x98/0x1e4
inet_twsk_kill tw atomic_read(&tw->tw_refcnt) 8, called from
call_timer_fn+0x98/0x1e4
__sock_put tw atomic_read(&tw->tw_refcnt) 8, called from
call_timer_fn+0x98/0x1e4
__sock_put tw atomic_read(&tw->tw_refcnt) 7, called from
inet_twsk_kill+0x104/0x148
inet_twsk_put tw atomic_read(&tw->tw_refcnt) 6, called from
call_timer_fn+0x98/0x1e4

CRs-Fixed: 1090436
Change-Id: Ib53c51baf351d851c33c196564be43508f531996
Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>