The value of tmnxMcLagConfigLagSystemPriority specifies the system
priority to be used in the context of mc-lag. The partner system will
consider all ports using the same system-id, system priority and
lacp-key as part of the same lag.
In order to achieve this in mc-lag operation, both systems have to be
configured with the same values.
A low numeric value specifies a high system priority.
The value of this object must be 0 when the value of
tLagStandbySignaling of the corresponding LAG is 'powerOff (2)'.
The value of this object cannot be 0 when the value of
tLagStandbySignaling of the corresponding LAG is 'lacp (1)'.