Fix RDB expiry write length and leak when loading zipmap (#3422)

Fix two things:

1. Incorrect RDB object size reported when writing hash fields with
expiration, because of wrong position of parentheses. Affects the
serialized size reported in DEBUG OBJECT.

2. Memory leak when loading a zipmap (only used in really old RDB
versions).

Signed-off-by: charsyam <charsyam@naver.com>
Co-authored-by: Harkrishn Patro <bunty.hari@gmail.com>

src/rdb.c

@@ -1018,7 +1018,7 @@ ssize_t rdbSaveObject(rio *rdb, robj *o, robj *key, int dbid, unsigned char rdbt
                 nwritten += n;
                 if (add_expiry) {
                     long long expiry = entryGetExpiry(next);
-                    if ((n = rdbSaveMillisecondTime(rdb, expiry) == -1)) {
+                    if ((n = rdbSaveMillisecondTime(rdb, expiry)) == -1) {
                         hashtableCleanupIterator(&iter);
                         return -1;
                     }
@@ -2414,6 +2414,7 @@ robj *rdbLoadObject(int rdbtype, rio *rdb, sds key, int dbid, int *error, int rd
                         hashtableRelease(dupSearchHashtable);
                         sdsfree(field);
                         zfree(encoded);
+                        zfree(lp);
                         objectSetVal(o, NULL);
                         decrRefCount(o);
                         return NULL;