net/mlx5e: Revert parameters on errors when changing MTU and LRO state without reset

Sometimes, channel params are changed without recreating the channels.
It happens in two basic cases: when the channels are closed, and when
the parameter being changed doesn't affect how channels are configured.
Such changes invoke a hardware command that might fail. The whole
operation should be reverted in such cases, but the code that restores
the parameters' values in the driver was missing. This commit adds this
handling.

Fixes: 2e20a151

 ("net/mlx5e: Fail safe mtu and lro setting")
Signed-off-by: Maxim Mikityanskiy <maximmi@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>