Remove extra ';' after member function definition. (#2780)

This fixes a clang compiler warning about extra semicolons.
diff --git a/source/opt/graphics_robust_access_pass.h b/source/opt/graphics_robust_access_pass.h
index f9d17ca..d330c9d 100644
--- a/source/opt/graphics_robust_access_pass.h
+++ b/source/opt/graphics_robust_access_pass.h
@@ -41,7 +41,7 @@
            IRContext::kAnalysisInstrToBlockMapping |
            IRContext::kAnalysisConstants | IRContext::kAnalysisTypes |
            IRContext::kAnalysisIdToFuncMapping;
-  };
+  }
 
  private:
   // Records failure for the current module, and returns a stream