tcp_comp: allow ignore local tcp connections

hulk inclusion
category: feature
bugzilla: NA
CVE: NA

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Tcp compression is used to reduce the amount of data transmitted
between multiple machines, which can increase the transmission
capacity.

The local tcp connection is a single machine transfer, so there
is no meaning to use tcp compression. Ignore it by default.

Enable by sysctl:

  echo 1 > /proc/net/ipv4/tcp_compression_local

Signed-off-by: Wang Hai <wanghai38@huawei.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Wang Yufen <wangyufen@huawei.com>
Reviewed-by: Wei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: Yue Haibing <yuehaibing@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>