luci-theme-material: do not show the message 'no password' on the login page

This note is also not displayed in the theme luci-theme-boostrap. Also, for
security reasons, we should not explicitly point this out on the login page,
that no password is set.

Signed-off-by: Florian Eckert <fe@dev.tdt.de>

themes/luci-theme-material/ucode/template/themes/material/header.ut

@@ -73,7 +73,7 @@
 		<div class="darkMask"></div>
 		<div id="maincontent">
 			<div class="container">
-				{% if (getuid() == 0 && getspnam('root')?.pwdp === ''): %}
+				{% if (getuid() == 0 && getspnam('root')?.pwdp === '' && ctx.authsession): %}
 					<div class="alert-message warning">
 						<h4>{{ _('No password set!') }}</h4>
 						<p>{{ _('There is no password set on this router. Please configure a root password to protect the web interface.') }}</p>