tree-wide: use IN_SET macro (#6977)

src/basic/parse-util.c

@@ -152,7 +152,7 @@ int parse_size(const char *t, uint64_t base, uint64_t *size) {
         unsigned n_entries, start_pos = 0;
 
         assert(t);
-        assert(base == 1000 || base == 1024);
+        assert(IN_SET(base, 1000, 1024));
         assert(size);
 
         if (base == 1000) {