s390: Fix ram_size updating in machine init

The global variable 'ram_size' is hidden by the local variable
declaration in s390_init(). Since we want to update the global
ram size in certain cases we must not use a local ram_size
variable.
- This fixes booting with unusual ram sizes like -m 67001
- This changes behaviour back to the situation before commit
  5f072e1f
  (create struct for machine initialization arguments)
Signed-off-by: NHeinz Graalfs <graalfs@linux.vnet.ibm.com>
Reviewed-by: NEduardo Habkost <ehabkost@redhat.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

hw/s390-virtio.c

@@ -155,7 +155,6 @@ unsigned s390_del_running_cpu(CPUS390XState *env)
 static void s390_init(QEMUMachineInitArgs *args)
 {
     ram_addr_t my_ram_size = args->ram_size;
-    ram_addr_t ram_size = args->ram_size;
     const char *cpu_model = args->cpu_model;
     const char *kernel_filename = args->kernel_filename;
     const char *kernel_cmdline = args->kernel_cmdline;