mlxsw: core: Extend EMAD information reported to devlink hwerr

Extend EMAD information reported to devlink hwerr tracepoint with
transaction id and reg id (both, hex and string).

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>