dma-buf: heaps: add parameter to account allocations using cgroup

dma-buf: heaps: add parameter to account allocations using cgroup

Add a parameter to enable dma-buf heaps allocation accounting using
cgroup for heaps that implement it. It is disabled by default as doing
so incurs caveats based on how memcg currently accounts for shared
buffers.

Signed-off-by: Eric Chanudet <echanude@redhat.com>
Reviewed-by: T.J. Mercier <tjmercier@google.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Link: https://patch.msgid.link/20260116-dmabuf-heap-system-memcg-v3-1-ecc6b62cc446@redhat.com