[clang][bytecode] Print field descriptor in Pointer::print() (llvm#168002)

This is almost always useful information and ::print() is debug-only
code.

Author: tbaederr

clang/lib/AST/ByteCode/Pointer.h

@@ -830,6 +830,9 @@ class Pointer {
 
 inline llvm::raw_ostream &operator<<(llvm::raw_ostream &OS, const Pointer &P) {
   P.print(OS);
+  OS << ' ';
+  if (const Descriptor *D = P.getFieldDesc())
+    D->dump(OS);
   return OS;
 }