s390x: fix -initrd in virtio machine

When using -initrd in the virtio machine, we need to indicate the initrd
start and size inside the kernel image. These parameters need to be stored
in native endianness.

Signed-off-by: Alexander Graf <agraf@suse.de>
Acked-by: Richard Henderson <rth@twiddle.net>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>

hw/s390-virtio.c

@@ -285,8 +285,8 @@ static void s390_init(QEMUMachineInitArgs *args)
         }
 
         /* we have to overwrite values in the kernel image, which are "rom" */
-        memcpy(rom_ptr(INITRD_PARM_START), &initrd_offset, 8);
-        memcpy(rom_ptr(INITRD_PARM_SIZE), &initrd_size, 8);
+        stq_p(rom_ptr(INITRD_PARM_START), initrd_offset);
+        stq_p(rom_ptr(INITRD_PARM_SIZE), initrd_size);
     }
 
     if (rom_ptr(KERN_PARM_AREA)) {