[POWERPC] disallow building powermac and tsi108 without PCI

The TSI108 code and the 32 bit powermac and chrp platforms
have dependency on PCI that is not easy or desirable to get rid
of.

The easiest fix is to always select CONFIG_PCI if one of those
platforms is enabled.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
diff --git a/arch/powerpc/platforms/embedded6xx/Kconfig b/arch/powerpc/platforms/embedded6xx/Kconfig
index 91a1652..bec7726 100644
--- a/arch/powerpc/platforms/embedded6xx/Kconfig
+++ b/arch/powerpc/platforms/embedded6xx/Kconfig
@@ -45,6 +45,7 @@
 config TSI108_BRIDGE
 	bool
 	depends on MPC7448HPC2 || PPC_HOLLY
+	select PCI
 	select MPIC
 	select MPIC_WEIRD
 	default y