ppc/8xxx: Refactor code to determine if PCI is enabled & agent/host

Refactor the code into a simple bitmask lookup table that determines if
a given PCI controller is enabled and if its in host/root-complex or
agent/end-point mode.

Each processor in the PQ3/MPC86xx family specified different encodings
for the cfg_host_agt[] and cfg_IO_ports[] boot strapping signals.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
diff --git a/cpu/mpc8xxx/Makefile b/cpu/mpc8xxx/Makefile
index 430a75f..5cb6814 100644
--- a/cpu/mpc8xxx/Makefile
+++ b/cpu/mpc8xxx/Makefile
@@ -11,6 +11,7 @@
 LIB	= $(obj)lib8xxx.a
 
 COBJS-y	+= cpu.o
+COBJS-$(CONFIG_PCI)	+= pci_cfg.o
 
 SRCS	:= $(START:.o=.S) $(SOBJS-y:.o=.S) $(COBJS-y:.o=.c)
 OBJS	:= $(addprefix $(obj),$(SOBJS-y) $(COBJS-y))