MDL-55517 theme_noname: Tweak the size of the username/passwords

They looked a bit to large on smaller screen sizes.

Also removed trailing whitespace from the template.

Part of MDL-55071

theme/noname/templates/core/login.mustache

@@ -28,9 +28,9 @@
             <div class="col-sm-6">
             {{/hasinstructions}}
             {{^hasinstructions}}
-            <div class="col-sm-8 offset-sm-2 col-lg-6 offset-lg-3">
+            <div class="col-sm-6 offset-sm-3 col-md-4 offset-md-4">
             {{/hasinstructions}}
-        
+
                 <h2 class="m-t-1">{{#str}} login {{/str}}</h2>
 
                 {{#cansignup}}
@@ -87,7 +87,7 @@
                     </div>
 
                 </form>
-                                    
+
                 {{#canloginasguest}}
                     <div class="m-t-2">
                         <p>{{#str}}someallowguest{{/str}}</p>