CVE-2017-5715 (Spectre v2 Intel)

Add field to access guest MSR_IA332_SPEC_CTRL and MSR_IA32_PRED_CMD state.
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Andy Whitcroft <apw@canonical.com>
(backported from commit f93ba2a9b5ab2c275e9adc10876cc0425a33eec0)
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Acked-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>