Add const to "DWARFDie &Die" in a few functions as they can't change the DWARFDie.

llvm-svn: 302471
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp b/llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp
index ec5fb08..8a54429 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp
@@ -23,7 +23,7 @@
 using namespace dwarf;
 using namespace object;
 
-void DWARFVerifier::verifyDebugInfoAttribute(DWARFDie &Die,
+void DWARFVerifier::verifyDebugInfoAttribute(const DWARFDie &Die,
                                              DWARFAttribute &AttrValue) {
   const auto Attr = AttrValue.Attr;
   switch (Attr) {
@@ -68,7 +68,7 @@
   }
 }
 
-void DWARFVerifier::verifyDebugInfoForm(DWARFDie &Die,
+void DWARFVerifier::verifyDebugInfoForm(const DWARFDie &Die,
                                         DWARFAttribute &AttrValue) {
   const auto Form = AttrValue.Value.getForm();
   switch (Form) {