Rev 2.0 updates processor stepping id to '4'.

It was necessary to rename some of the Tukwila pins for syntax reasons.  The complete list follows:

TESTHI[1]    -> TESTHI[2]
TESTHI[2]    -> TESTHI[3]
TRIGGER[0]_N -> TRIGGER_N[0]
TRIGGER[1]_N -> TRIGGER_N[1]
ERROR[0]_N   -> ERROR_N[0]
ERROR[1]_N   -> ERROR_N[1]

