qemuMigrationPrecreateStorage: Fix debug message

When pre-creating storage for domains, we need to find corresponding
disk in the XML on the destination (domain XML may differ there, e.g.
disk is accessible under different path). For better debugging, I'm
printing all info I received on a disk. But there was a typo when
printing the disk capacity: "%lluu" instead of "%llu".
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
(cherry picked from commit 65a88572)

src/qemu/qemu_migration.c

@@ -1580,7 +1580,7 @@ qemuMigrationPrecreateStorage(virConnectPtr conn,
         int indx;
         const char *diskSrcPath;
 
-        VIR_DEBUG("Looking up disk target '%s' (capacity=%lluu)",
+        VIR_DEBUG("Looking up disk target '%s' (capacity=%llu)",
                   nbd->disks[i].target, nbd->disks[i].capacity);
 
         if ((indx = virDomainDiskIndexByName(vm->def,