Merge pull request #34900 from rxwei/ad-context-destructor

[AutoDiff] Properly destruct 'AutoDiffLinearMapContext'.

Author: rxwei

stdlib/public/runtime/AutoDiffSupport.cpp

@@ -19,6 +19,7 @@ using namespace llvm;
 
 SWIFT_CC(swift)
 static void destroyLinearMapContext(SWIFT_CONTEXT HeapObject *obj) {
+  static_cast<AutoDiffLinearMapContext *>(obj)->~AutoDiffLinearMapContext();
   free(obj);
 }