mlxsw: core: Extend hwmon interface with QSFP module temperature attributes

mlxsw: core: Extend hwmon interface with QSFP module temperature attributes

Add new attributes to hwmon object for exposing QSFP module temperature
input, fault indication, critical and emergency thresholds. Temperature
input and fault indication are read from Management Temperature Bulk
Register. Temperature thresholds are read from Management Cable Info
Access Register.

Signed-off-by: Vadim Pasternak <vadimp@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>