elua: include fork_win.c in compilation

src/bin/elua/fork_win.c

@@ -109,7 +109,7 @@ static int init_ntdll(void) {
     return !!ZwCreateProcess;
 }
 
-int fork_win(void) {
+static int fork_win(void) {
     if (setjmp(jenv)) return 0;
     if (!ZwCreateProcess && !init_ntdll()) return -1;
 

src/bin/elua/main.c

@@ -8,6 +8,7 @@
 #define pipe(x, mode) pipe(x)
 #else
 #include <io.h>
+#include "fork_win.c"
 int fork_win(void);
 #define fork fork_win
 #define fdopen _fdopen