Silence flexelint warnings

bin/varnishd/storage/storage_simple.c

@@ -197,10 +197,12 @@ sml_slim(struct worker *wrk, struct objcore *oc)
 	CHECK_OBJ_NOTNULL(o, OBJECT_MAGIC);
 
 #define OBJ_AUXATTR(U, l)					\
+	do {							\
 		if (o->aa_##l != NULL) {			\
 			sml_stv_free(stv, o->aa_##l);		\
 			o->aa_##l = NULL;			\
-	}
+		}						\
+	} while (0);
 #include "tbl/obj_attr.h"
 
 	VTAILQ_FOREACH_SAFE(st, &o->list, list, stn) {
@@ -689,7 +691,9 @@ SML_panic(struct vsb *vsb, const struct objcore *oc)
 	    #U, o->va_##l##_len, o->va_##l);
 
 #define OBJ_AUXATTR(U, l)						\
-	if (o->aa_##l != NULL) sml_panic_st(vsb, #U, o->aa_##l);
+        do {								\
+		if (o->aa_##l != NULL) sml_panic_st(vsb, #U, o->aa_##l);\
+	} while(0);
 
 #include "tbl/obj_attr.h"