net/mlx5e: TC, Move pedit_headers_action to parse_attr

net/mlx5e: TC, Move pedit_headers_action to parse_attr

Move pedit_headers_action from flow parse_state to flow parse_attr.
In a follow up commit we are going to have multiple attr per flow
and pedit_headers_action are unique per attr.

Signed-off-by: Roi Dayan <[email protected]>
Reviewed-by: Oz Shlomo <[email protected]>
Reviewed-by: Maor Dickman <[email protected]>
Signed-off-by: Saeed Mahameed <[email protected]>