Clean up all places in exception.S that fiddle with 'pcpup' directly. We now use the GET_CPU_PCPU() macro exclusively.
Clean up all places in exception.S that fiddle with 'pcpup' directly. We now
use the GET_CPU_PCPU() macro exclusively.

This isolates the users of pcpu data from its implementation details.

Reviewed by: imp

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase