drm/radeon: clean up encoder dp checks

Use the proper struct in the union.  That field
has the same offset in every struct, so no functional
change.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This commit is contained in:
Alex Deucher 2012-09-06 12:26:09 -04:00
commit 2f6fa79a7e