Use 'override/final' instead of 'virtual' for overridden methods

The patch is generated using clang-tidy misc-use-override check.

This command was used:

  tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py \
    -checks='-*,misc-use-override' -header-filter='llvm|clang' \
    -j=32 -fix -format

http://reviews.llvm.org/D8925



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234679 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/Option/ArgList.h

@@ -320,7 +320,7 @@ private:
 
 public:
   InputArgList(const char* const *ArgBegin, const char* const *ArgEnd);
-  ~InputArgList();
+  ~InputArgList() override;
 
   const char *getArgString(unsigned Index) const override {
     return ArgStrings[Index];
@@ -355,7 +355,7 @@ class DerivedArgList : public ArgList {
 public:
   /// Construct a new derived arg list from \p BaseArgs.
   DerivedArgList(const InputArgList &BaseArgs);
-  ~DerivedArgList();
+  ~DerivedArgList() override;
 
   const char *getArgString(unsigned Index) const override {
     return BaseArgs.getArgString(Index);