microblaze: Fix pci compilation and sparse warnings

Warning log:
  CHECK   arch/microblaze/pci/pci-common.c
arch/microblaze/pci/pci-common.c:290:14: warning: Using plain integer as NULL pointer
arch/microblaze/pci/pci-common.c:1127:6: warning: symbol
'pcibios_allocate_bus_resources' was not declared. Should it be static?
arch/microblaze/pci/pci-common.c:1436:61: warning: incorrect type in argument 3 (different base types)
arch/microblaze/pci/pci-common.c:1436:61:    expected unsigned int [unsigned] [usertype] offset
arch/microblaze/pci/pci-common.c:1436:61:    got void [noderef] <asn:2>*
  CC      arch/microblaze/pci/pci-common.o
arch/microblaze/pci/pci-common.c: In function 'pci_proc_domain':
arch/microblaze/pci/pci-common.c:825:25: warning: unused variable 'hose' [-Wunused-variable]
arch/microblaze/pci/pci-common.c: In function 'pcibios_allocate_bus_resources':
arch/microblaze/pci/pci-common.c:1182:1: warning: label 'clear_resource' defined but not used [-Wunused-label]
arch/microblaze/pci/pci-common.c: In function 'pcibios_setup_phb_resources':
arch/microblaze/pci/pci-common.c:1436:2: warning: passing argument 3 of
'pci_add_resource_offset' makes integer from pointer without a cast [enabled by default]
include/linux/pci.h:999:6: note: expected 'resource_size_t' but argument is of type 'void *'

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/arch/microblaze/pci/pci-common.c b/arch/microblaze/pci/pci-common.c
index a1c5b99..e84b129 100644
--- a/arch/microblaze/pci/pci-common.c
+++ b/arch/microblaze/pci/pci-common.c
@@ -287,7 +287,7 @@
 	unsigned long io_offset = 0;
 	int i, res_bit;
 
-	if (hose == 0)
+	if (!hose)
 		return NULL;		/* should never happen */
 
 	/* If memory, add on the PCI bridge address offset */
@@ -822,8 +822,6 @@
 /* Decide whether to display the domain number in /proc */
 int pci_proc_domain(struct pci_bus *bus)
 {
-	struct pci_controller *hose = pci_bus_to_host(bus);
-
 	return 0;
 }
 
@@ -1124,7 +1122,7 @@
  *	    as well.
  */
 
-void pcibios_allocate_bus_resources(struct pci_bus *bus)
+static void pcibios_allocate_bus_resources(struct pci_bus *bus)
 {
 	struct pci_bus *b;
 	int i;
@@ -1179,7 +1177,7 @@
 		}
 		printk(KERN_WARNING "PCI: Cannot allocate resource region "
 		       "%d of PCI bridge %d, will remap\n", i, bus->number);
-clear_resource:
+
 		res->start = res->end = 0;
 		res->flags = 0;
 	}
@@ -1433,7 +1431,8 @@
 		res->end = res->start + IO_SPACE_LIMIT;
 		res->flags = IORESOURCE_IO;
 	}
-	pci_add_resource_offset(resources, res, hose->io_base_virt - _IO_BASE);
+	pci_add_resource_offset(resources, res,
+		(__force resource_size_t)(hose->io_base_virt - _IO_BASE));
 
 	pr_debug("PCI: PHB IO resource    = %016llx-%016llx [%lx]\n",
 		 (unsigned long long)res->start,