net/mlx5e: Geneve, Add support for encap/decap flows offload

Add HW offloading support for flows with Geneve encap/decap.

Notes about decap flows with Geneve TLV Options:
  - Support offloading of 32-bit options data only
  - At any given time, only one combination of class/type parameters
    can be offloaded, but the same class/type combination can have
    many different flows offloaded with different 32-bit option data
  - Options with value of 0 can't be offloaded

Reviewed-by: Oz Shlomo <ozsh@mellanox.com>
Signed-off-by: Yevgeny Kliteynik <kliteyn@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>