healthd: Turn on -Werror

Change-Id: I72caf38008ee7d842dfacd3f58add9bc8e4787e8
diff --git a/healthd/BatteryPropertiesRegistrar.cpp b/healthd/BatteryPropertiesRegistrar.cpp
index 272b6d7..74bcbfd 100644
--- a/healthd/BatteryPropertiesRegistrar.cpp
+++ b/healthd/BatteryPropertiesRegistrar.cpp
@@ -76,7 +76,7 @@
     return healthd_get_property(id, val);
 }
 
-status_t BatteryPropertiesRegistrar::dump(int fd, const Vector<String16>& args) {
+status_t BatteryPropertiesRegistrar::dump(int fd, const Vector<String16>& /*args*/) {
     IPCThreadState* self = IPCThreadState::self();
     const int pid = self->getCallingPid();
     const int uid = self->getCallingUid();