media: venus: hfi_cmds: struct hfi_session_release_buffer_pkt: Add __counted_by annotation

The only direct user of struct hfi_session_release_buffer_pkt is
pkt_session_unset_buffers() which sets "num_buffers" before using it
as a loop counter for accessing "buffer_info". Add the __counted_by
annotation to reflect the relationship.

Reviewed-by: Vikash Garodia <quic_vgarodia@quicinc.com>
Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Reviewed-by: Dikshita Agarwal <quic_dikshita@quicinc.com>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20240710230914.3156277-2-kees@kernel.org


Signed-off-by: Kees Cook <kees@kernel.org>