At91SamSdio: Add support for SAM3U4E.
At91SamSdio: Add support for SAM3U4E.

johnkingsley/aprinter,johnkingsley/aprinter,johnkingsley/aprinter,ambrop72/aprinter,ambrop72/aprinter,ambrop72/aprinter,ambrop72/aprinter,johnkingsley/aprinter,johnkingsley/aprinter,ambrop72/aprinter,ambrop72/aprinter,johnkingsley/aprinter,ambrop72/aprinter,johnkingsley/aprinter