Ensure /etc/make.conf file is present.

The file is required to be present in order for the file_line resource
to work correctly. Add require to ensure the file is created before the
WITH_PKGNG is attempted to be set.

manifests/init.pp

@@ -20,9 +20,14 @@ class pkgng (
       notify   => Exec['pkg update'],
     }
 
+    file { "/etc/make.conf":
+      ensure => present,
+    }
+
     file_line { "WITH_PKGNG":
       path => '/etc/make.conf',
       line => "WITH_PKGNG=yes\n",
+      require => File['/etc/make.conf'],
     }
 
     # Triggered on config changes