mount: don't close a namespace descriptor two times

CID null (#1 of 1): Double close (USE_AFTER_FREE)
10. double_close: Calling "restore_ns(int, struct ns_desc *)" closes
handle "ns_old" which has already been closed.

Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
check: Soft-dirty support is upstream since v3.11

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
zdtm: increase the upstream kernel version

The kernel must be 3.11 or greater due to
29000cae ptrace: add ability to get/set signal-blocked mask (v2)

The patches for dumping tun devices are not committed in the upstream
kernel yet, so ns/static/tun is excluded.

Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
parasite: take into account the fact that a file descriptor can be zero

6. Condition "rst > 0", taking false branch
7. off_by_one: Testing whether handle "rst" is strictly greater than
   zero is suspicious. Did you intend to include equality with zero?
   "rst" leaks when it is zero.

CID 1072986 (#3 of 4): Resource leak (RESOURCE_LEAK)
12. leaked_handle: Handle variable "rst" going out of scope leaks the
handle.

Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
criu: Version 0.7 release

* Quite a lot of bugfixes and improvements in documentation, thanks to
feedback from users.

* New notable features include TUN devices, shared and master/slave
mounts and alternative signal stack (sigaltstack) support.

* Memory tracking is now upstream.

* This is the last release, that is tied to kernel release. The next
one will happen as soon as we decide it's worth doing so, not after
the linux-3.12.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>