mlxsw: spectrum: Add Spectrum-2 ASIC port type-speed operations

Add Spectrum-2 ASIC port type-speed operations.

Since multiple ethtool link modes are represented using a single bit in the
ASIC, the driver forces the user to configure all types per a specific
speed. For example, if the user wants to advertise 100Gbps 4-lanes speed,
he should advertise all the types of 100Gbps 4-lanes speed that are
supported by the ASIC as shown below:

  Supported ethtool bits for 100Gbps 4-lanes:
      0x1000000000      100000baseKR4 Full
      0x2000000000      100000baseSR4 Full
      0x4000000000      100000baseCR4 Full
      0x8000000000      100000baseLR4_ER4 Full

  Command for advertising 100Gbps 4-lanes:
      ethtool -s enp3s0np1 advertise 0xF000000000
Signed-off-by: Shalom Toledo <shalomt@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlxsw/spectrum.h

@@ -34,6 +34,7 @@
 #define MLXSW_SP_PORTS_PER_CLUSTER_MAX 4
 
 #define MLXSW_SP_PORT_BASE_SPEED_25G 25000 /* Mb/s */
+#define MLXSW_SP_PORT_BASE_SPEED_50G 50000 /* Mb/s */
 
 #define MLXSW_SP_KVD_LINEAR_SIZE 98304 /* entries */
 #define MLXSW_SP_KVD_GRANULARITY 128