lockdep/selftest: Add more recursive read related test cases

Add those four test cases:

1.	X --(ER)--> Y --(ER)--> Z --(ER)--> X is deadlock.

2.	X --(EN)--> Y --(SR)--> Z --(ER)--> X is deadlock.

3.	X --(EN)--> Y --(SR)--> Z --(SN)--> X is not deadlock.

4.	X --(ER)--> Y --(SR)--> Z --(EN)--> X is not deadlock.

Those self testcases are valuable for the development of supporting
recursive read related deadlock detection.

Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200807074238.1632519-17-boqun.feng@gmail.com
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