msys2: Fix absolute windows paths

- Ensure path DATA_DIR isn't made absolute during compilation
- Use cygpath to create absolute path at runtime

src/altera.cpp

@@ -13,6 +13,7 @@
 #include "device.hpp"
 #include "epcq.hpp"
 #include "progressBar.hpp"
+#include "pathHelper.hpp"
 #include "rawParser.hpp"
 
 #define IDCODE 6
@@ -181,6 +182,11 @@ bool Altera::load_bridge()
 	bitname += _device_package + ".rbf";
 #endif
 
+#if defined (_WIN64) || defined (_WIN32)
+	/* Convert relative path embedded at compile time to an absolute path */
+	bitname = PathHelper::absolutePath(bitname);
+#endif
+
 	std::cout << "use: " << bitname << std::endl;
 
 	/* first: load spi over jtag */