Add BIOS attribute hb_mirror_memory

Hostboot reads hb_mirror_memory and sets ATTR_PAYLOAD_IN_MIRROR_MEM

Signed-off-by: Chen Du <duchen@us.ibm.com>
Change-Id: I2efad571ad22c568c8a8a0110ffb0759af3b948e
diff --git a/oem/ibm/configurations/bios/enum_attrs.json b/oem/ibm/configurations/bios/enum_attrs.json
index 74151ba..1629d64 100644
--- a/oem/ibm/configurations/bios/enum_attrs.json
+++ b/oem/ibm/configurations/bios/enum_attrs.json
@@ -264,6 +264,30 @@
          ],
          "helpText" : "Specifies whether the secure version lockin functionality is enabled.",
          "displayName" : "Secure Version Lockin Enabled"
+      },
+      {
+         "attribute_name":"hb_mirror_memory_mode",
+         "possible_values":[
+            "Disabled",
+            "Enabled"
+         ],
+         "default_values":[
+            "Enabled"
+         ],
+         "helpText" : "Specifies if the memory mirroring is enabled, requires a reboot for a change to be applied.",
+         "displayName" : "Mirror Memory Mode (pending)"
+      },
+      {
+         "attribute_name":"hb_mirror_memory_mode_current",
+         "possible_values":[
+            "Disabled",
+            "Enabled"
+         ],
+         "default_values":[
+            "Enabled"
+         },
+         "helpText" : "Specifies if the memory mirroring is enabled for the current IPL. Do not set this attribute directly; set hb_mirror_memory_mode instead.",
+         "displayName" : "Mirror Memory Mode (current)"
       }
    ]
 }