merge the template and non-template versions of attacks_bb
If we tell the compiler to inline properly, we can pass constexpr parameters of a function call as arguments instead of having to use templates, with no performance loss.
passed non-reg STC: https://tests.stockfishchess.org/tests/view/6aa791c9a8284b37a0a05cd2
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 112544 W: 28589 L: 28463 D: 55492
Ptnml(0-2): 162, 11683, 32439, 11843, 145
closes https://github.com/official-stockfish/Stockfish/pull/7171
No functional change