use favicon by default

cgit.c

@@ -363,6 +363,7 @@ static void prepare_context(struct cgit_context *ctx)
 	ctx->cfg.commit_sort = 0;
 	ctx->cfg.css = "/cgit.css";
 	ctx->cfg.logo = "/cgit.png";
+	ctx->cfg.favicon = "/favicon.ico";
 	ctx->cfg.local_time = 0;
 	ctx->cfg.enable_http_clone = 1;
 	ctx->cfg.enable_index_owner = 1;

cgitrc.5.txt

@@ -172,9 +172,9 @@ enable-git-config::
 	scan-path, section-from-path.
 
 favicon::
-	Url used as link to a shortcut icon for cgit. If specified, it is
-	suggested to use the value "/favicon.ico" since certain browsers will
-	ignore other values. Default value: none.
+	Url used as link to a shortcut icon for cgit. It is suggested to use
+	the value "/favicon.ico" since certain browsers will ignore other
+	values. Default value: "/favicon.ico".
 
 footer::
 	The content of the file specified with this option will be included