Cleanup includes

Reorder a few includes, include "position.h" where it was previously missing
and apply include-what-you-use suggestions. Also make the order of the includes
consistent, in the following way:

1. Related header (for .cpp files)
2. A blank line
3. C/C++ headers
4. A blank line
5. All other header files

closes https://github.com/official-stockfish/Stockfish/pull/4763
fixes https://github.com/official-stockfish/Stockfish/issues/4707

No functional change

src/syzygy/tbprobe.cpp

@@ -16,33 +16,38 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
+#include "tbprobe.h"
+
+#include <sys/stat.h>
 #include <algorithm>
 #include <atomic>
+#include <cassert>
 #include <cstdint>
-#include <cstring>   // For std::memset and std::memcpy
+#include <cstdlib>
+#include <cstring>
 #include <deque>
 #include <fstream>
+#include <initializer_list>
 #include <iostream>
-#include <list>
 #include <mutex>
 #include <sstream>
 #include <string_view>
 #include <type_traits>
+#include <utility>
+#include <vector>
 
 #include "../bitboard.h"
+#include "../misc.h"
 #include "../movegen.h"
 #include "../position.h"
 #include "../search.h"
 #include "../types.h"
 #include "../uci.h"
 
-#include "tbprobe.h"
-
 #ifndef _WIN32
 #include <fcntl.h>
-#include <unistd.h>
 #include <sys/mman.h>
-#include <sys/stat.h>
+#include <unistd.h>
 #else
 #define WIN32_LEAN_AND_MEAN
 #ifndef NOMINMAX
@@ -1002,7 +1007,7 @@ uint8_t* set_sizes(PairsData* d, uint8_t* data) {
     // Starting from this we compute a base64[] table indexed by symbol length
     // and containing 64 bit values so that d->base64[i] >= d->base64[i+1].
 
-    // Implementation note: we first cast the unsigned size_t "base64.size()" 
+    // Implementation note: we first cast the unsigned size_t "base64.size()"
     // to a signed int "base64_size" variable and then we are able to subtract 2,
     // avoiding unsigned overflow warnings.