[analyzer][MallocChecker][NFC] Change the use of IdentifierInfo* to CallDescription

Exactly what it says on the tin! I decided not to merge this with the patch that
changes all these to a CallDescriptionMap object, so the patch is that much more
trivial.

Differential Revision: https://reviews.llvm.org/D68163

Author: Szelethus

clang/include/clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h

@@ -258,6 +258,13 @@ class CallEvent {
   /// calls.
   bool isCalled(const CallDescription &CD) const;
 
+  /// Returns true whether the CallEvent is any of the CallDescriptions supplied
+  /// as a parameter.
+  template <typename FirstCallDesc, typename... CallDescs>
+  bool isCalled(const FirstCallDesc &First, const CallDescs &... Rest) const {
+    return isCalled(First) || isCalled(Rest...);
+  }
+
   /// Returns a source range for the entire call, suitable for
   /// outputting in diagnostics.
   virtual SourceRange getSourceRange() const {