providers/virtualbox: fix broken NFS check

lib/vagrant/action/builtin/synced_folders.rb

@@ -44,7 +44,7 @@ module Vagrant
 
               if File.directory?(data[:hostpath])
                 data[:hostpath] = File.realpath(data[:hostpath])
-                data[:hostpath] = Util::Platform.fs_real_path(data[:hostpath])
+                data[:hostpath] = Util::Platform.fs_real_path(data[:hostpath]).to_s
               end
             end
           end

plugins/providers/virtualbox/action.rb

@@ -59,9 +59,9 @@ module VagrantPlugins
           b.use PrepareForwardedPortCollisionParams
           b.use HandleForwardedPortCollisions
           b.use PruneNFSExports
-          b.use PrepareNFSSettings
           b.use ClearSharedFolders
           b.use SyncedFolders
+          b.use PrepareNFSSettings
           b.use ClearNetworkInterfaces
           b.use Network
           b.use ForwardPorts

plugins/providers/virtualbox/action/prepare_nfs_settings.rb

@@ -12,7 +12,7 @@ module VagrantPlugins
 
           using_nfs = false
           env[:machine].config.vm.synced_folders.each do |id, opts|
-            if opts[:nfs]
+            if opts[:type] == :nfs
               using_nfs = true
               break
             end