Nullability check for sem module.

Bugs: b/245972273
Test: adb shell
Change-Id: Ie29aa34c449300c53591557c99b6ec08ebe3efcf
diff --git a/tests/sys_sem_test.cpp b/tests/sys_sem_test.cpp
index b98926b..4bac92f 100644
--- a/tests/sys_sem_test.cpp
+++ b/tests/sys_sem_test.cpp
@@ -87,15 +87,21 @@
 }
 
 TEST(sys_sem, semop_failure) {
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wnonnull"
   errno = 0;
   ASSERT_EQ(-1, semop(-1, nullptr, 0));
   ASSERT_TRUE(errno == EINVAL || errno == ENOSYS);
+#pragma clang diagnostic pop
 }
 
 TEST(sys_sem, semtimedop_failure) {
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wnonnull"
   errno = 0;
   ASSERT_EQ(-1, semtimedop(-1, nullptr, 0, nullptr));
   ASSERT_TRUE(errno == EINVAL || errno == ENOSYS);
+#pragma clang diagnostic pop
 }
 
 TEST(sys_sem, union_semun) {