[POWERPC] Split powermac platforms into their own Kconfig file

Cleaning up arch/powerpc/Kconfig platform support.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

arch/powerpc/Kconfig

@@ -433,25 +433,7 @@ config PPC_CHRP
 	default y
 
 source "arch/powerpc/platforms/52xx/Kconfig"
-
-config PPC_PMAC
-	bool "Apple PowerMac based machines"
-	depends on PPC_MULTIPLATFORM
-	select MPIC
-	select PPC_INDIRECT_PCI if PPC32
-	select PPC_MPC106 if PPC32
-	select PPC_NATIVE
-	default y
-
-config PPC_PMAC64
-	bool
-	depends on PPC_PMAC && POWER4
-	select MPIC
-	select U3_DART
-	select MPIC_BROKEN_U3
-	select GENERIC_TBSYNC
-	select PPC_970_NAP
-	default y
+source "arch/powerpc/platforms/powermac/Kconfig"
 
 config PPC_PREP
 	bool "PowerPC Reference Platform (PReP) based machines"

arch/powerpc/platforms/powermac/Kconfig

+config PPC_PMAC
+	bool "Apple PowerMac based machines"
+	depends on PPC_MULTIPLATFORM
+	select MPIC
+	select PPC_INDIRECT_PCI if PPC32
+	select PPC_MPC106 if PPC32
+	select PPC_NATIVE
+	default y
+
+config PPC_PMAC64
+	bool
+	depends on PPC_PMAC && POWER4
+	select MPIC
+	select U3_DART
+	select MPIC_BROKEN_U3
+	select GENERIC_TBSYNC
+	select PPC_970_NAP
+	default y
+
+