Enable lmkd kill tracing everywhere

Test: asdf
Exempt-From-Owner-Approval: vacation
Change-Id: If6af7df74d303466aac4a69cdfe558e9748f72b9
diff --git a/lmkd/lmkd.c b/lmkd/lmkd.c
index c514bc3..74454de 100644
--- a/lmkd/lmkd.c
+++ b/lmkd/lmkd.c
@@ -55,8 +55,8 @@
 
 #else /* LMKD_TRACE_KILLS */
 
-#define TRACE_KILL_START(pid)
-#define TRACE_KILL_END()
+#define TRACE_KILL_START(pid) ((void)(pid))
+#define TRACE_KILL_END() ((void)0)
 
 #endif /* LMKD_TRACE_KILLS */