ppc64: Add support for PowerMacs in the OF client interface code (prom.c)

Also move some of the init cruft into separate function to make
things slightly more readable. We sill need to significantly
cleanup that file, but that will come later...

Properly export the OF device-tree accessors to modules

include/asm-ppc64/lmb.h

@@ -23,6 +23,7 @@ extern unsigned long reloc_offset(void);
 union lmb_reg_property { 
 	struct reg_property32	 addr32[MAX_LMB_REGIONS];
 	struct reg_property64	 addr64[MAX_LMB_REGIONS];
+	struct reg_property_pmac addrPM[MAX_LMB_REGIONS];
 };
 
 #define LMB_MEMORY_AREA	1

include/asm-ppc64/prom.h

@@ -108,6 +108,12 @@ struct reg_property64 {
 	unsigned long size;
 };
 
+struct reg_property_pmac {
+	unsigned int address_hi;
+	unsigned int address_lo;
+	unsigned int size;
+};
+
 struct translation_property {
 	unsigned long virt;
 	unsigned long size;
@@ -207,6 +213,7 @@ struct prom_args {
 
 struct prom_t {
 	unsigned long entry;
+	ihandle root;
 	ihandle chosen;
 	int cpu;
 	ihandle stdout;