Wherein the TargetInfo argument to Preprocessor is made 'const' and propogated.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@87087 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Lex/Preprocessor.cpp b/lib/Lex/Preprocessor.cpp
index 0110e6b..96c6682 100644
--- a/lib/Lex/Preprocessor.cpp
+++ b/lib/Lex/Preprocessor.cpp
@@ -44,7 +44,7 @@
 //===----------------------------------------------------------------------===//
 
 Preprocessor::Preprocessor(Diagnostic &diags, const LangOptions &opts,
-                           TargetInfo &target, SourceManager &SM,
+                           const TargetInfo &target, SourceManager &SM,
                            HeaderSearch &Headers,
                            IdentifierInfoLookup* IILookup,
                            bool OwnsHeaders)