dma-buf: Always build with DMABUF_MOVE_NOTIFY

dma-buf: Always build with DMABUF_MOVE_NOTIFY

DMABUF_MOVE_NOTIFY was introduced in 2018 and has been marked as
experimental and disabled by default ever since. Six years later,
all new importers implement this callback.

It is therefore reasonable to drop CONFIG_DMABUF_MOVE_NOTIFY and
always build DMABUF with support for it enabled.

Suggested-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://lore.kernel.org/r/20260124-dmabuf-revoke-v5-3-f98fca917e96@nvidia.com
Signed-off-by: Christian König <christian.koenig@amd.com>