i386: Add new MSR indices for IA32_PRED_CMD and IA32_ARCH_CAPABILITIES

IA32_PRED_CMD MSR gives software a way to issue commands that affect the state
of indirect branch predictors. Enumerated by CPUID.(EAX=7H,ECX=0):EDX[26].
IA32_ARCH_CAPABILITIES MSR enumerates architectural features of RDCL_NO and
IBRS_ALL. Enumerated by CPUID.(EAX=07H, ECX=0):EDX[29].

https://software.intel.com/sites/default/files/managed/c5/63/336996-Speculative-Execution-Side-Channel-Mitigations.pdfSigned-off-by: NRobert Hoo <robert.hu@linux.intel.com>
Message-Id: <1530781798-183214-2-git-send-email-robert.hu@linux.intel.com>
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>

target/i386/cpu.h

@@ -354,6 +354,8 @@ typedef enum X86Seg {
 #define MSR_TSC_ADJUST                  0x0000003b
 #define MSR_IA32_SPEC_CTRL              0x48
 #define MSR_VIRT_SSBD                   0xc001011f
+#define MSR_IA32_PRED_CMD               0x49
+#define MSR_IA32_ARCH_CAPABILITIES      0x10a
 #define MSR_IA32_TSCDEADLINE            0x6e0
 
 #define FEATURE_CONTROL_LOCKED                    (1<<0)