cpu: quiesce pseudoinsts: Always do full quiesce

cpu: quiesce pseudoinsts: Always do full quiesce

The O3CPU blocks the Fetch when it sees a quiesce instruction (IsQuiesce flag).
When the inst. is executed, a quiesce event is created to reactivate the
context and unblock the Fetch.

If the quiesceNs or quiesceCycles are called with a value of 0, the
QuiesceEvent will not be created and the Fetch stage will remain blocked.

Committed by Joel Hestness <jthestness@gmail.com>