add example for mismatched deallocation class in documentation

Author: pskrgag

clang/docs/analyzer/checkers/mismatched_deallocator_example.cpp

@@ -6,6 +6,10 @@ void test() {
 
 // C, C++
 void __attribute((ownership_returns(malloc))) *user_malloc(size_t);
+void __attribute((ownership_takes(malloc, 1))) *user_free(void *);
+
+void __attribute((ownership_returns(malloc1))) *user_malloc1(size_t);
+void __attribute((ownership_takes(malloc1, 1))) *user_free1(void *);
 
 void test() {
   int *p = (int *)user_malloc(sizeof(int));
@@ -24,6 +28,12 @@ void test() {
   realloc(p, sizeof(long)); // warn
 }
 
+// C, C++
+void test() {
+  int *p = user_malloc(10);
+  user_free1(p); // warn
+}
+
 // C, C++
 template <typename T>
 struct SimpleSmartPointer {