initialize only ACPI_BUFFER to avoid race condition with passive cooling thread which refers psv, tc1, tc2 and tsp.  The previous code made the period where sc->tz_zone.tsp was zero, and it caused panic at msleep().
initialize only ACPI_BUFFER to avoid race condition with passive
cooling thread which refers psv, tc1, tc2 and tsp.  The previous
code made the period where sc->tz_zone.tsp was zero, and it caused
panic at msleep().

Reported by:	keramida
Tested by:	keramida

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