wallet: fix null column access for pre-0.7.3 dbs.

Added in d901304120, this column is null in old dbs like mine:

2020-02-15T00:08:41.444Z **BROKEN** database: Accessing a null column 12 in query SELECT  id, channel_htlc_id, msatoshi, cltv_expiry, hstate, payment_hash, payment_key, routing_onion, failuremsg, malformed_onion, origin_htlc, shared_secret, received_time FROM channel_htlcs WHERE direction= ? AND channel_id= ? AND hstate != ?

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Makefile

@@ -49,7 +49,7 @@ endif
 
 ifeq ($(COMPAT),1)
 # We support compatibility with pre-0.6.
-COMPAT_CFLAGS=-DCOMPAT_V052=1 -DCOMPAT_V060=1 -DCOMPAT_V061=1 -DCOMPAT_V062=1 -DCOMPAT_V070=1 -DCOMPAT_V073=1 -DCOMPAT_V080=1
+COMPAT_CFLAGS=-DCOMPAT_V052=1 -DCOMPAT_V060=1 -DCOMPAT_V061=1 -DCOMPAT_V062=1 -DCOMPAT_V070=1 -DCOMPAT_V072=1 -DCOMPAT_V073=1 -DCOMPAT_V080=1
 endif
 
 # Timeout shortly before the 600 second travis silence timeout

wallet/wallet.c

@@ -1831,6 +1831,12 @@ static bool wallet_stmt2htlc_in(struct channel *channel,
 #endif
 	}
 
+#ifdef COMPAT_V072
+	if (db_column_is_null(stmt, 12)) {
+		in->received_time.ts.tv_sec = 0;
+		in->received_time.ts.tv_nsec = 0;
+	} else
+#endif /* COMPAT_V072 */
 	in->received_time = db_column_timeabs(stmt, 12);
 
 	return ok;