commit 9200ee49 upstream.

vbios says external TMDS while the board is actually
internal TMDS.

fixes:
https://bugs.freedesktop.org/show_bug.cgi?id=60037Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>