Fix after r308190.

[amccarth]

Summary

Update some LLDB code after clang::MacroInfo::arg_iterator was
reandmed to param_iterator.

[faisalv]

sorry my refactoring broke it - but thanks for the fix!

[amccarth]

Beaten to it by r308219.

lldb/source/Plugins/ExpressionParser/Clang/ClangModulesDeclVendor.cpp

if (macro_info) {
       macro_expansion.append(mi->first->getName().str());
 
       {
         if (macro_info->isFunctionLike()) {
           macro_expansion.append("(");
 
           bool first_arg = true;
 
-          for (clang::MacroInfo::arg_iterator ai = macro_info->arg_begin(),
-                                              ae = macro_info->arg_end();
-               ai != ae; ++ai) {
+          for (clang::MacroInfo::param_iterator pi = macro_info->param_begin(),
+                                                pe = macro_info->param_end();
+               pi != pe; ++pi) {
             if (!first_arg) {
               macro_expansion.append(", ");
             } else {
               first_arg = false;
             }
 
-            macro_expansion.append((*ai)->getName().str());
+            macro_expansion.append((*pi)->getName().str());
           }
 
           if (macro_info->isC99Varargs()) {
             if (first_arg) {
               macro_expansion.append("...");
             } else {
               macro_expansion.append(", ...");
             }