drm/amd/display: Fix memoryleak during S3 resume.

Do not create dc_state within display_resume, since it's being
constructed within atomic check.

Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Leo (Sunpeng) Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>