Drop -Wno-unused-parameter.

The only one left is libedify. Will handle that in a separate CL.

Test: mmma bootable/recovery
Change-Id: I732a5f85229da90fd767bee2e46c5c95f529c396
diff --git a/wear_ui.cpp b/wear_ui.cpp
index e2ee488..ca6b1b1 100644
--- a/wear_ui.cpp
+++ b/wear_ui.cpp
@@ -150,8 +150,7 @@
   gr_flip();
 }
 
-void WearRecoveryUI::SetStage(int current, int max) {
-}
+void WearRecoveryUI::SetStage(int /* current */, int /* max */) {}
 
 void WearRecoveryUI::StartMenu(const char* const* headers, const char* const* items,
                                int initial_selection) {