net/mlx5e: Fix modify header actions memory leak

Modify header actions are allocated during parse tc actions and only
freed during the flow creation, however, on error flow the allocated
memory is wrongly unfreed.

Fix this by calling dealloc_mod_hdr_actions in __mlx5e_add_fdb_flow
and mlx5e_add_nic_flow error flow.

Fixes: d7e75a32 ("net/mlx5e: Add offloading of E-Switch TC pedit (header re-write) actions")
Fixes: 2f4fe4ca

 ("net/mlx5e: Add offloading of NIC TC pedit (header re-write) actions")
Signed-off-by: Maor Dickman <maord@nvidia.com>
Reviewed-by: Paul Blakey <paulb@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>