Remove useless casts.

Signed-off-by: Garrett Cooper <yanegomi@gmail.com>
diff --git a/testcases/kernel/syscalls/signalfd4/signalfd4_02.c b/testcases/kernel/syscalls/signalfd4/signalfd4_02.c
index caa6c06..08e30b1 100644
--- a/testcases/kernel/syscalls/signalfd4/signalfd4_02.c
+++ b/testcases/kernel/syscalls/signalfd4/signalfd4_02.c
@@ -136,8 +136,8 @@
 	char *msg;		/* message returned from parse_opts */
 
 	/* Parse standard options given to run the test. */
-	msg = parse_opts(argc, argv, (option_t *) NULL, NULL);
-	if (msg != (char *)NULL) {
+	msg = parse_opts(argc, argv, NULL, NULL);
+	if (msg != NULL) {
 		tst_brkm(TBROK, NULL, "OPTION PARSING ERROR - %s", msg);
 		tst_exit();
 	}