Apple TouchBar icon Support (mask-icon) (#5159)

* Update index.html

Add Apple TouchBar icon Color Support

* Add svg icon

* Change path to SVG icon

* Rename mask-icon.svg to home-assistant-icon.svg

* Remove useless whitespace

* Update index.html

homeassistant/components/frontend/templates/index.html

@@ -8,6 +8,7 @@
     <link rel='icon' href='/static/icons/favicon.ico'>
     <link rel='apple-touch-icon' sizes='180x180'
           href='/static/icons/favicon-apple-180x180.png'>
+    <link rel="mask-icon" href="/static/icons/home-assistant-icon.svg" color="#3fbbf4">
     {% for panel in panels.values() -%}
       <link rel='prefetch' href='{{ panel.url }}'>
     {% endfor -%}