socket: skipe unsupported sockets (v2)
socket: skipe unsupported sockets (v2)

We collect all unix sockets in the current net namespace, but
a target process uses a few of them, so we may skip unsupported sockets
and if it is used by a target process, lookup_socket returns error.

Signed-off-by: Andrey Vagin <74c05afa918858348d6db8037d82fa8124870113@openvz.org>
Acked-by: Pavel Emelyanov <c9a32589e048e044184536f7ac71ef92fe82df3e@parallels.com>
Signed-off-by: Cyrill Gorcunov <7a1ea01eee6961eb1e372e3508c2670446d086f4@openvz.org>

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