[llvm-objcopy] Fix a warningon unused variable. NFC.

llvm-svn: 372745
diff --git a/llvm/tools/llvm-objcopy/CopyConfig.cpp b/llvm/tools/llvm-objcopy/CopyConfig.cpp
index 1425321..9929166 100644
--- a/llvm/tools/llvm-objcopy/CopyConfig.cpp
+++ b/llvm/tools/llvm-objcopy/CopyConfig.cpp
@@ -386,7 +386,7 @@
                            .Case("ihex", FileFormat::IHex)
                            .Default(FileFormat::Unspecified);
 
-  if (opt::Arg *A = InputArgs.getLastArg(OBJCOPY_new_symbol_visibility))
+  if (InputArgs.hasArg(OBJCOPY_new_symbol_visibility))
     Config.NewSymbolVisibility =
         InputArgs.getLastArgValue(OBJCOPY_new_symbol_visibility);