Fix warnings

Author: fjtrujy

examples/logo/logo.cpp

@@ -43,7 +43,7 @@ struct rtHeader {
  * prototypes
  */
 
-rtHeader* LoadRTexFile(char* fileName, unsigned int texName);
+rtHeader* LoadRTexFile(const char* fileName, unsigned int texName);
 ps2glMeshHeader* LoadMesh(const char* fileName);
 void DrawMesh(const void* header);