Remove two unused member variables.

They were added over 10 years ago in r66575 and have never been used as
far as I can tell.

(r67087 added similar fields to Compilation, and those are used.)

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@365638 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/Driver/Driver.h

@@ -235,9 +235,6 @@ private:
   /// Certain options suppress the 'no input files' warning.
   unsigned SuppressMissingInputWarning : 1;
 
-  std::list<std::string> TempFiles;
-  std::list<std::string> ResultFiles;
-
   /// Cache of all the ToolChains in use by the driver.
   ///
   /// This maps from the string representation of a triple to a ToolChain