macro for free_struct()

diff --git a/skeletons/constr_CHOICE.c b/skeletons/constr_CHOICE.c
index 33cec7e..26fd8dd 100644
--- a/skeletons/constr_CHOICE.c
+++ b/skeletons/constr_CHOICE.c
@@ -959,10 +959,10 @@
 		if(elm->flags & ATF_POINTER) {
 			memb_ptr = *(void **)((char *)ptr + elm->memb_offset);
 			if(memb_ptr)
-				elm->type->free_struct(elm->type, memb_ptr, 0);
+				ASN_STRUCT_FREE(*elm->type, memb_ptr);
 		} else {
 			memb_ptr = (void *)((char *)ptr + elm->memb_offset);
-			elm->type->free_struct(elm->type, memb_ptr, 1);
+			ASN_STRUCT_FREE_CONTENTS_ONLY(*elm->type, memb_ptr);
 		}
 	}