docs($location.ihshprfx): remove docs for unused error

docs/content/error/$location/ihshprfx.ngdoc

@@ -1,17 +0,0 @@
-@ngdoc error
-@name $location:ihshprfx
-@fullName Missing Hash Prefix
-@description
-
-This error occurs when {@link ng.$location $location} service is configured to use a hash prefix but this prefix was not present in a url that the `$location` service was asked to parse.
-
-For example if you configure `$location` service with prefix `'!'`:
-```
-myApp.config(function($locationProvider) {
-  $locationProvider.hashPrefix('!');
-});
-```
-
-If you enter the app at url `http://myapp.com/#/myView` this error will be thrown.
-
-The correct url for this configuration is `http://myapp.com/#!/myView` (note the `'!'` after `'#'` symbol).