MdeModulePkg/Partition: Fix media probe
    
    The call in ProbeMediaStatusEx() to the ReadDisk() function of the
    EFI_DISK_IO_PROTOCOL interface implemented in DiskIoDxe/DiskIo.c
    crashed in DiskIo2ReadWriteDisk() because of the NULL value of
    the destination buffer pointer.
    
    Pass the address of a buffer in the stack instead of a NULL
    pointer.
    
    The similar fix was applied to ProbeMediaStatus in commit
    df473cc1fc9acd1a623ec7e05276f2f0635c19d2
    * MdeModulePkg/PartitionDxe: Fix media probe
    
    Somehow ProbeMediaStatusEx() wasn't changed together.
    
    Contributed-under: TianoCore Contribution Agreement 1.1
    Signed-off-by: Ruiyu Ni <ruiyu.ni@intel.com>
    Reviewed-by: Jian J Wang <jian.j.wang@intel.com>
    Tested-by: Jian J Wang <jian.j.wang@intel.com>