powerpc/eeh: Move common part to kernel directory

The patch moves the common part of EEH core into arch/powerpc/kernel
directory so that we needn't PPC_PSERIES while compiling POWERNV
platform:

        * Move the EEH common part into arch/powerpc/kernel
        * Move the functions for PCI hotplug from pSeries platform to
          arch/powerpc/kernel/pci-hotplug.c
        * Move CONFIG_EEH from arch/powerpc/platforms/pseries/Kconfig to
          arch/powerpc/platforms/Kconfig
        * Adjust makefile accordingly

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/platforms/Kconfig b/arch/powerpc/platforms/Kconfig
index b62aab3..bed8c60 100644
--- a/arch/powerpc/platforms/Kconfig
+++ b/arch/powerpc/platforms/Kconfig
@@ -164,6 +164,11 @@
 	help
 	  Bus device driver for GX bus based adapters.
 
+config EEH
+	bool
+	depends on (PPC_POWERNV || PPC_PSERIES) && PCI
+	default y
+
 config PPC_MPC106
 	bool
 	default n