qemu: address: Remove dead code when un-reserving PCI address

The code can't fail so having error handling is pointless.

src/conf/domain_addr.c

@@ -687,12 +687,11 @@ virDomainPCIAddressEnsureAddr(virDomainPCIAddressSetPtr addrs,
 }
 
 
-int
+void
 virDomainPCIAddressReleaseAddr(virDomainPCIAddressSetPtr addrs,
                                virPCIDeviceAddressPtr addr)
 {
     addrs->buses[addr->bus].slot[addr->slot].functions &= ~(1 << addr->function);
-    return 0;
 }
 
 virDomainPCIAddressSetPtr

src/conf/domain_addr.h

@@ -166,8 +166,8 @@ int virDomainPCIAddressEnsureAddr(virDomainPCIAddressSetPtr addrs,
                                   virDomainPCIConnectFlags flags)
     ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2);
 
-int virDomainPCIAddressReleaseAddr(virDomainPCIAddressSetPtr addrs,
-                                   virPCIDeviceAddressPtr addr)
+void virDomainPCIAddressReleaseAddr(virDomainPCIAddressSetPtr addrs,
+                                    virPCIDeviceAddressPtr addr)
     ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2);
 
 void virDomainPCIAddressSetAllMulti(virDomainDefPtr def)

src/qemu/qemu_domain_address.c

@@ -2892,11 +2892,8 @@ qemuDomainReleaseDeviceAddress(virDomainObjPtr vm,
     if (!devstr)
         devstr = info->alias;
 
-    if (virDeviceInfoPCIAddressPresent(info) &&
-        virDomainPCIAddressReleaseAddr(priv->pciaddrs,
-                                       &info->addr.pci) < 0)
-        VIR_WARN("Unable to release PCI address on %s",
-                 NULLSTR(devstr));
+    if (virDeviceInfoPCIAddressPresent(info))
+        virDomainPCIAddressReleaseAddr(priv->pciaddrs, &info->addr.pci);
 
     if (info->type == VIR_DOMAIN_DEVICE_ADDRESS_TYPE_USB &&
         priv->usbaddrs &&