drm/amd/display: Store tiling_flags in the framebuffer.

This moves the tiling_flags to the framebuffer creation.
This way the time of the "tiling" decision is the same as it
would be with modifiers.

Signed-off-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>