mlxsw: reg: Spectrum-3: Enforce lowest max-shaper burst size of 11

A max-shaper is the HW component responsible for delaying egress traffic
above a configured transmission rate. Burst size is the amount of traffic
that is allowed to pass without accounting. The burst size value needs to
be such that it can be expressed as 2^BS * 512 bits, where BS lies in a
certain ASIC-dependent range. mlxsw enforces that this holds before
attempting to configure the shaper.

The assumption for Spectrum-3 was that the lower limit of BS would be 5,
like for Spectrum-1. But as of now, the limit is still 11. Therefore fix
the driver accordingly, so that incorrect values are rejected early with a
proper message.

Fixes: 23effa24 ("mlxsw: reg: Add max_shaper_bs to QoS ETS Element Configuration")
Reported-by: Maksym Yaremchuk <maksymy@nvidia.com>
Signed-off-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>