s390/pci: add missing pci_iov.h include

this fixes a missing prototype compiler warning spotted by the kernel
test robot.

Fixes: abb95b75 ("s390/pci: consolidate SR-IOV specific code")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

arch/s390/pci/pci_iov.c

@@ -13,6 +13,8 @@
 #include <linux/kernel.h>
 #include <linux/pci.h>
 
+#include "pci_iov.h"
+
 static struct resource iov_res = {
 	.name	= "PCI IOV res",
 	.start	= 0,