fix native Windows build

For some reason, Cygwin's MinGW-W64 compilers end up pulling in our
version of process.h from unistd.h.  That doesn't really make sense --
it should use the one from the sysroot, but we can work around it by
just not including unistd.h, since it's not needed on Windows anyway.

src/binaryToObject/main.cpp

@@ -18,9 +18,9 @@
 #include <windows.h>
 #else
 #include <sys/mman.h>
+#include <unistd.h>
 #endif
 #include <fcntl.h>
-#include <unistd.h>
 
 #include "tools.h"