libcontainer: add support for Landlock #7229

Job	Run time
cross-i386	22s
test (ubuntu-20.04, 1.22.x, rootless, -race)	24s
test (ubuntu-20.04, 1.22.x, rootless)	26s
test (ubuntu-20.04, 1.22.x, -race)	23s
test (ubuntu-20.04, 1.22.x)	25s
test (ubuntu-20.04, 1.23.x, rootless, -race)	23s
test (ubuntu-20.04, 1.23.x, rootless)	24s
test (ubuntu-20.04, 1.23.x, -race)	25s
test (ubuntu-20.04, 1.23.x)	22s
test (ubuntu-20.04, 1.23.x, criu-dev)	1m 19s
test (ubuntu-24.04, 1.22.x, rootless, -race)	1m 4s
test (ubuntu-24.04, 1.22.x, rootless)	41s
test (ubuntu-24.04, 1.22.x, -race)	32s
test (ubuntu-24.04, 1.22.x)	33s
test (ubuntu-24.04, 1.23.x, rootless, -race)	40s
test (ubuntu-24.04, 1.23.x, rootless)	1m 17s
test (ubuntu-24.04, 1.23.x, -race)	39s
test (ubuntu-24.04, 1.23.x)	36s
test (ubuntu-24.04, 1.23.x, criu-dev)	1m 3s
test (actuated-arm64-6cpu-8gb, 1.23.x, rootless)	38s
test (actuated-arm64-6cpu-8gb, 1.23.x)	33s
all-done	0s
	13m 9s

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