Temporary revert "Expose EvalInfo struct to search"

It is not needed for the release and introduces
a slowdown, although very small.

Probably it will be readded after the release.

No functional change.

src/search.h

@@ -25,7 +25,6 @@
 #include <stack>
 #include <vector>
 
-#include "evaluate.h"
 #include "misc.h"
 #include "position.h"
 #include "types.h"
@@ -49,7 +48,6 @@ struct Stack {
   Value evalMargin;
   int skipNullMove;
   int futilityMoveCount;
-  Eval::Info ei;
 };