Patch by Yuli Barcohen, 7 Aug 2003:

According to the MPC8260 User's Manual, PCI_MODE signal should be
reflected in SCCR register, and local bus pins configuration is taken
from HRCW and appears in SIUMCR. For some reason it does not work
this way, so the only possibility to detect if the board is
configured in PCI mode is to check the BCSR. This patch sets SCCR and
SIUMCR according to the BCSR.