Split first 3 boards

Also introduce board executor file. Renamed w10dll splits.

src/REL/board_executor.c

@@ -0,0 +1,23 @@
+#include "REL/board_executor.h"
+
+static void InitBoard(void) {
+    BoardCommonInit(BoardInit, BoardDestroy);
+}
+
+int _prolog(void) {
+    const VoidFunc* ctors = _ctors;
+    while (*ctors != 0) {
+        (**ctors)();
+        ctors++;
+    }
+	InitBoard();
+    return 0;
+}
+
+void _epilog(void) {
+    const VoidFunc* dtors = _dtors;
+    while (*dtors != 0) {
+        (**dtors)();
+        dtors++;
+    }
+}