Chess engine: Stockfish 20021515

Stockfish - UCI chess engine, compiled by Joost VandeVondele

Timestamp: 1581775807
Fix for incorrect VALUE_MATE_IN_MAX_PLY usage.
Fixes #2533, fixes #2543, fixes #2423.

the code that prevents false mate announcements depending on the TT state (GHI), incorrectly used VALUE_MATE_IN_MAX_PLY. The latter constant, however, also includes, counterintuitively, the TB win range.

This patch fixes that, by restoring the behavior for TB win scores, while retaining the false mate correctness, and improving the mate finding ability. In particular no alse mates are announced with the poisened hash testcase
```
position fen 8/8/8/3k4/8/8/6K1/7R w - - 0 1
go depth 40
position fen 8/8/8/3k4/8/8/6K1/7R w - - 76 1
go depth 20
ucinewgame
```

mates are found with the testcases reported in #2543
```
position fen 4k3/3pp3/8/8/8/8/2PPP3/4K3 w - - 0 1
setoption name Hash value 1024
go depth 55
ucinewgame
```
and
```
position fen 4k3/4p3/8/8/8/8/3PP3/4K3 w - - 0 1
setoption name Hash value 1024
go depth 45
ucinewgame
```

furthermore, on the mate finding benchmark (ChestUCI_23102018.epd),
performance improves over master, roughly reaching performance with the
false mate protection reverted
```
Analyzing 6566 mate positions for best and found mates:

----------------best ---------------found
nodes master revert fixed master revert fixed
16000000 4233 4236 4235 5200 5201 5199
32000000 4583 4585 4585 5417 5424 5418
64000000 4852 4853 4855 5575 5584 5579
128000000 5071 5068 5066 5710 5720 5716
256000000 5280 5282 5279 5819 5827 5826
512000000 5471 5468 5468 5919 5935 5932
```

On a testcase with TB enabled, progress is made consistently, contrary to master
```
setoption name SyzygyPath value ../../../syzygy/3-4-5/
setoption name Hash value 2048 position fen 1R6/3k4/8/K2p4/4n3/2P5/8/8 w - - 0 1
go depth 58 ucinewgame
```

The PR (prior to a rewrite for clarity)
passed STC:
LLR: 2.94 (-2.94,2.94) {-1.50,0.50}
Total: 65405 W: 12454 L: 12384 D: 40567 Elo +0.37
Ptnml(0-2): 920, 7256, 16285, 7286, 944
http://tests.stockfishchess.org/tests/view/5e441a3be70d848499f63d15

passed LTC:
LLR: 2.94 (-2.94,2.94) {-1.50,0.50}
Total: 27096 W: 3477 L: 3413 D: 20206 Elo +0.82
Ptnml(0-2): 128, 2215, 8776, 2292, 122
http://tests.stockfishchess.org/tests/view/5e44e277e70d848499f63d63

The incorrectly named VALUE_MATE_IN_MAX_PLY and VALUE_MATED_IN_MAX_PLY
were renamed into VALUE_TB_WIN_IN_MAX_PLY and VALUE_TB_LOSS_IN_MAX_PLY,
and correclty defined VALUE_MATE_IN_MAX_PLY and VALUE_MATED_IN_MAX_PLY
were introduced.

One further (corner case) mistake using these constants was fixed (go mate X), which could lead to a premature return if X > MAX_PLY / 2, but TB were present.

Thanks to @svivanov72 for one of the reports and help fixing the issue.
closes https://github.com/official-stockfish/Stockfish/pull/2552
Bench: 4932981

Stockfish 20021515 download