Fix build warnings: ignoring return value of ‘chdir’,

declared with attribute warn_unused_result

src/terminal-screen.c

@@ -230,7 +230,8 @@ cwd_of_pid (int pid)
 				if (chdir (cwd_file) == 0)
 				{
 					working_dir = g_get_current_dir ();
-					(void) chdir (cwd);
+					if (chdir (cwd) < 0)
+						g_warning ("Could not change working directory.");
 				}
 				g_free (cwd);
 			}

src/terminal.c

@@ -563,7 +563,8 @@ main (int argc, char **argv)
 	 */
 	home_dir = g_get_home_dir ();
 	if (home_dir == NULL || chdir (home_dir) < 0)
-		(void) chdir ("/");
+		if (chdir ("/") < 0)
+			g_warning ("Could not change working directory.");
 
 	options = terminal_options_parse (working_directory,
 	                                  NULL,