This option is added together with scsi-disk but is never honoured,
becuase we don't emulate the VPD page for scsi-block. We could intercept
and inject the user specified value like for max xfer len, but it's
probably not helpful since the intent of 070f8009 was for random
entropy aspects, not for performance. If emulated rotation rate is
desired, scsi-hd is more suitable.

Signed-off-by: Fam Zheng <famz@redhat.com>

Message-Id: <20180917083138.3948-1-famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>