lightningd: keep pid files in top-level config dir.

They're already qualified with network name, and there's little point
moving them; it might even be dangerous if multiple are running.

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

lightningd/options.c

@@ -862,10 +862,12 @@ static void promote_missing_files(struct lightningd *ld)
 	while ((d = readdir(d_from)) != NULL) {
 		const char *fullname;
 
-		/* Ignore this directory and upper one, and leave config */
+		/* Ignore this directory and upper one, and leave
+		 * config and pid files */
 		if (streq(d->d_name, ".")
 		    || streq(d->d_name, "..")
-		    || streq(d->d_name, "config"))
+		    || streq(d->d_name, "config")
+		    || strends(d->d_name, ".pid"))
 			continue;
 
 		fullname = path_join(tmpctx, "..", d->d_name);
@@ -965,7 +967,7 @@ void handle_early_opts(struct lightningd *ld, int argc, char *argv[])
 				 ld->config_dir);
 
 	/* Set default PID file name to be per-network */
-	ld->pidfile = tal_fmt(ld, "lightningd-%s.pid",
+	ld->pidfile = tal_fmt(ld, "../lightningd-%s.pid",
 			      chainparams->network_name);
 
 	/*~ Move into config dir: this eases path manipulation and also