use cgit_httpscheme() for atom feed
diff --git a/ui-atom.c b/ui-atom.c
index a6ea3ee..e5c31d9 100644
--- a/ui-atom.c
+++ b/ui-atom.c
@@ -52,7 +52,8 @@
 	cgit_print_date(info->author_date, FMT_ATOMDATE, ctx.cfg.local_time);
 	html("</published>\n");
 	if (host) {
-		html("<link rel='alternate' type='text/html' href='http://");
+		html("<link rel='alternate' type='text/html' href='");
+		html(cgit_httpscheme());
 		html_attr(host);
 		html_attr(cgit_pageurl(ctx.repo->url, "commit", NULL));
 		if (ctx.cfg.virtual_root)
@@ -113,7 +114,8 @@
 	html_txt(ctx.repo->desc);
 	html("</subtitle>\n");
 	if (host) {
-		html("<link rel='alternate' type='text/html' href='http://");
+		html("<link rel='alternate' type='text/html' href='");
+		html(cgit_httpscheme());
 		html_attr(host);
 		html_attr(cgit_repourl(ctx.repo->url));
 		html("'/>\n");