Increase base time use and limit max used.

Increase base time use and limit max used.

This change increases the base part of optimumTime at all depths. It also reduces the size of max_scale and thus maximumTime by using a linear scale instead of pow(x, 0.3) and by limiting max_scale to no more than 7 (previously as high as 8 or 9 at very high depths).

Tested using the closedpos book:

STC 10+0.1:
LLR: 2.94 (-2.94,2.94) {-0.50,1.50}
Total: 83696 W: 16813 L: 16508 D: 50375
Ptnml(0-2): 1315, 9649, 19686, 9812, 1386
https://tests.stockfishchess.org/tests/view/5ebfa92de9d85f94dc42989b

LTC 60+0.6:
LLR: 2.95 (-2.94,2.94) {0.25,1.75}
Total: 39384 W: 5868 L: 5582 D: 27934
Ptnml(0-2): 276, 3697, 11489, 3925, 305
https://tests.stockfishchess.org/tests/view/5ec0a6dce9d85f94dc42995a

Test for non-regression:

STC Sudden Death 10+0 :
LLR: 2.94 (-2.94,2.94) {-2.00,0.00}
Total: 111976 W: 25661 L: 25768 D: 60547
Ptnml(0-2): 2567, 13420, 24118, 13319, 2564
https://tests.stockfishchess.org/tests/view/5ec23b3be9d85f94dc429a58

closes  https://github.com/official-stockfish/Stockfish/pull/2685

Bench 4395562