net/mlx5e: Fix skb memory leak when TC classifier action offloads are disabled

When TC classifier action offloads are disabled (CONFIG_MLX5_CLS_ACT in
Kconfig), the mlx5e_rep_tc_receive() function which is responsible for
passing the skb to the stack (or freeing it) is defined as a nop, and
results in leaking the skb memory. Replace the nop with a call to
napi_gro_receive() to resolve the leak.

Fixes: 28e7606f ("net/mlx5e: Refactor rx handler of represetor device")
Signed-off-by: Gal Pressman <gal@nvidia.com>
Reviewed-by: Ariel Levkovich <lariel@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>