drm/amd/display: Minor code style change

This commit adds some minor code style changes just to reduce the merge
conflicts we have when we upstream some of the VBA code.

Reviewed-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>