PCI Hotplug: move pci_hotplug.h to include/linux/

This makes it possible to build pci hotplug drivers outside of the main
kernel tree, and Sam keeps telling me to move local header files to
their proper places...

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h
index 30f021c..4fb12fc 100644
--- a/drivers/pci/hotplug/pciehp.h
+++ b/drivers/pci/hotplug/pciehp.h
@@ -31,11 +31,11 @@
 
 #include <linux/types.h>
 #include <linux/pci.h>
+#include <linux/pci_hotplug.h>
 #include <linux/delay.h>
 #include <linux/sched.h>		/* signal_pending() */
 #include <linux/pcieport_if.h>
 #include <linux/mutex.h>
-#include "pci_hotplug.h"
 
 #define MY_NAME	"pciehp"