drm/radeon: add connector table for SAM440ep embedded board

commit 6a556039e7823d27a0a7f7724d4d455053ea9253 upstream.

RV250 found on ppc embedded boards.

Cc: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Weng Meiling <wengmeiling.weng@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>