add common function library

src/app/core/common.h

@@ -0,0 +1,17 @@
+#ifndef YAZE_CORE_COMMON_H
+#define YAZE_CORE_COMMON_H
+
+#include <cstdint>
+
+namespace yaze {
+namespace app {
+namespace core {
+
+unsigned int SnesToPc(unsigned int addr);
+int AddressFromBytes(uint8_t addr1, uint8_t addr2, uint8_t addr3);
+
+}  // namespace core
+}  // namespace app
+}  // namespace premia
+
+#endif