Add BPF-helper test case for CLOCK_TAI access. The added test verifies that:
* Timestamps are generated
* Timestamps are moving forward
* Timestamps are reasonable
Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
Link: https://lore.kernel.org/r/20220809060803.5773-3-kurt@linutronix.de
Signed-off-by: Alexei Starovoitov <ast@kernel.org>