amdgpu/dc: don't memset after kzalloc.
We allocate this struct zeroed, so don't need to memset in the
constructor.
Signed-off-by: Dave Airlie <airlied@redhat.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>