common/gossip_store: fix lseek argument order on gossip_store reload.

We don't currently use this, but it's badly wrong.

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

common/gossip_store.c

@@ -147,10 +147,10 @@ u8 *gossip_store_next(const tal_t *ctx, struct per_peer_state *pps)
 void gossip_store_switch_fd(struct per_peer_state *pps,
 			    int newfd, u64 offset_shorter)
 {
-	u64 cur = lseek(pps->gossip_store_fd, SEEK_CUR, 0);
+	u64 cur = lseek(pps->gossip_store_fd, 0, SEEK_CUR);
 
 	/* If we're already at end (common), we know where to go in new one. */
-	if (cur == lseek(pps->gossip_store_fd, SEEK_END, 0)) {
+	if (cur == lseek(pps->gossip_store_fd, 0, SEEK_END)) {
 		status_debug("gossip_store at end, new fd moved to %"PRIu64,
 			     cur - offset_shorter);
 		assert(cur > offset_shorter);