net/mlx5e: Pass old channels as argument to mlx5e_switch_priv_channels

net/mlx5e: Pass old channels as argument to mlx5e_switch_priv_channels

Let the caller function mlx5e_safe_switch_params() maintain a copy
of the old channels, and pass it to mlx5e_switch_priv_channels().

This is in preparation for the next patch.

Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Carolina Jubran <cjubran@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/1761831159-1013140-7-git-send-email-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>