look in /usr/share/games/simutrans for game data

@DPATCH@

--- simutrans.orig/simmain.cc
+++ simutrans/simmain.cc
@@ -437,8 +437,9 @@
 		strcat( umgebung_t::program_dir, path_sep );
 	}
 	else {
-		strcpy( umgebung_t::program_dir, argv[0] );
-		*(strrchr( umgebung_t::program_dir, path_sep[0] )+1) = 0;
+		// strcpy( umgebung_t::program_dir, argv[0] );
+		// *(strrchr( umgebung_t::program_dir, path_sep[0] )+1) = 0;
+		strcpy(umgebung_t::program_dir, "/usr/share/games/simutrans/");
 
 		chdir( umgebung_t::program_dir );
 	}