[Quasar] Fix ThreadId enum

[amokanTT]

The ThreadId enum needs to be added to /tt_llk_quasar/common/inc/ckernel_defs.h in order to bring up Quasar in metal in PR #1145 .

However this enum has values which are misleading, for istance BriscThreadId. Brisc does not exist in Quasar and this enum should be refactored.

enum ThreadId
{
    BriscThreadId  = 0,
    UnpackThreadId = 1,
    MathThreadId   = 2,
    PackThreadId   = 3
};