[PATCH] powerpc: IBMEBUS bus support

This patch adds the necessary core bus support used by device drivers
that sit on the IBM GX bus on modern pSeries machines like the Galaxy
infiniband for example. It provide transparent DMA ops (the low level
driver works with virtual addresses directly) along with a simple bus
layer using the Open Firmware matching routines.

Signed-off-by: Heiko J Schick <schickhj@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>