posix: sched: Implement tests for set APIs for scheduling parameters

Implement tests for `sched_setparam()` and `sched_setscheduler()` .
Both functions are actually placeholders and just return `ENOSYS`
since Zephyr does not yet support processes or process scheduling.

signed-off-by: Gaetan Perrot <gaetanperrotpro@gmail.com>

tests/posix/common/src/pthread.c

@@ -405,6 +405,28 @@ ZTEST(pthread, test_sched_getscheduler)
 
 	zassert_true((rc == -1 && err == ENOSYS));
 }
+ZTEST(pthread, test_sched_setparam)
+{
+	struct sched_param param = {
+		.sched_priority = 2,
+	};
+	int rc = sched_setparam(0, &param);
+	int err = errno;
+
+	zassert_true((rc == -1 && err == ENOSYS));
+}
+
+ZTEST(pthread, test_sched_setscheduler)
+{
+	struct sched_param param = {
+		.sched_priority = 2,
+	};
+	int policy = 0;
+	int rc = sched_setscheduler(0, policy, &param);
+	int err = errno;
+
+	zassert_true((rc == -1 && err == ENOSYS));
+}
 
 ZTEST(pthread, test_pthread_equal)
 {

tests/posix/headers/src/sched_h.c

@@ -35,8 +35,8 @@ ZTEST(posix_headers, test_sched_h)
 
 		/* zassert_not_null(sched_rr_get_interval); */ /* not implemented */
 
-		/* zassert_not_null(sched_setparam); */ /* not implemented */
-		/* zassert_not_null(sched_setscheduler); */ /* not implemented */
+		zassert_not_null(sched_setparam);
+		zassert_not_null(sched_setscheduler);
 
 		zassert_not_null(sched_yield);
 	}