sfc: Move EF100 efx_nic_type structs to the end of the file

This avoids a forward declaration in a subsequent patch.
Signed-off-by: Jonathan Cooper <jonathan.s.cooper@amd.com>
Co-developed-by: Martin Habets <habetsm.xilinx@gmail.com>
Signed-off-by: Martin Habets <habetsm.xilinx@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>