Fixed an error reported by gcc on Fedora about format-security (#373)

This fixes something that is neither invalid nor a security vulnerability, Still, distros other than Fedora may decide to report it in the future as an error too. So we are getting ahead of them.

src/SDL/MyOpenGLView.m

@@ -324,7 +324,7 @@ - (id) init
 	}
 
 	int testAttrib = -1;
-	OOLog(@"display.initGL", @"Achieved color / depth buffer sizes (bits):");
+	OOLog(@"display.initGL", @"%@", @"Achieved color / depth buffer sizes (bits):");
 	SDL_GL_GetAttribute(SDL_GL_RED_SIZE, &testAttrib);
 	OOLog(@"display.initGL", @"Red: %d", testAttrib);
 	SDL_GL_GetAttribute(SDL_GL_GREEN_SIZE, &testAttrib);