net/mlx5e: CT: Make mlx5_ct_fs_smfs_ct_validate_flow_rule reusable

net/mlx5e: CT: Make mlx5_ct_fs_smfs_ct_validate_flow_rule reusable

This function checks whether a flow_rule has the right flow dissector
keys and masks used for a connection tracking flow offload. It is
currently used locally by the tc_ct smfs module, but is about to be used
from another place, so this commit moves it to a better place, renames
it to mlx5e_tc_ct_is_valid_flow_rule and drops the unused fs argument.

Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>
Reviewed-by: Jianbo Liu <jianbol@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://patch.msgid.link/20250114130646.1937192-4-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>