Make SMDiagnostic::Print a const method.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94672 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/SourceMgr.cpp b/lib/Support/SourceMgr.cpp
index 7652e18..83c7964 100644
--- a/lib/Support/SourceMgr.cpp
+++ b/lib/Support/SourceMgr.cpp
@@ -188,7 +188,7 @@
 // SMDiagnostic Implementation
 //===----------------------------------------------------------------------===//
 
-void SMDiagnostic::Print(const char *ProgName, raw_ostream &S) {
+void SMDiagnostic::Print(const char *ProgName, raw_ostream &S) const {
   if (ProgName && ProgName[0])
     S << ProgName << ": ";