sparc64: Fix build errors with gcc-4.6.0

Most of the warnings emitted (we fail arch/sparc file
builds with -Werror) were legitimate but harmless, however
one case (n2_pcr_write) was a genuine bug.

Based almost entirely upon a patch by Sam Ravnborg.

Reported-by: Dennis Gilmore <dennis@ausil.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/arch/sparc/kernel/pci_common.c b/arch/sparc/kernel/pci_common.c
index 6c7a33a..6e3874b 100644
--- a/arch/sparc/kernel/pci_common.c
+++ b/arch/sparc/kernel/pci_common.c
@@ -295,14 +295,17 @@
 	unsigned int bus = bus_dev->number;
 	unsigned int device = PCI_SLOT(devfn);
 	unsigned int func = PCI_FUNC(devfn);
-	unsigned long ret;
 
 	if (config_out_of_range(pbm, bus, devfn, where)) {
 		/* Do nothing. */
 	} else {
-		ret = pci_sun4v_config_put(devhandle,
-				HV_PCI_DEVICE_BUILD(bus, device, func),
-				where, size, value);
+		/* We don't check for hypervisor errors here, but perhaps
+		 * we should and influence our return value depending upon
+		 * what kind of error is thrown.
+		 */
+		pci_sun4v_config_put(devhandle,
+				     HV_PCI_DEVICE_BUILD(bus, device, func),
+				     where, size, value);
 	}
 	return PCIBIOS_SUCCESSFUL;
 }