PEL: Support for CheckstopFlag msg reg field

Similiar to the DeconfigFlag field that was recently added, this one
indicates the PEL is for a hardware checkstop and results in a bit in
SRC hex word 5 being set.

Signed-off-by: Matt Spinler <spinler@us.ibm.com>
Change-Id: Ib05de7471ad3e32f48e7f20a5c611abc119fe82a
diff --git a/extensions/openpower-pels/registry/schema/schema.json b/extensions/openpower-pels/registry/schema/schema.json
index 11885e5..4c548e5 100644
--- a/extensions/openpower-pels/registry/schema/schema.json
+++ b/extensions/openpower-pels/registry/schema/schema.json
@@ -102,7 +102,9 @@
 
                 "Words6To9": { "$ref": "#/definitions/srcWords6To9" },
 
-                "DeconfigFlag": { "$ref": "#/definitions/deconfigFlag" }
+                "DeconfigFlag": { "$ref": "#/definitions/deconfigFlag" },
+
+                "CheckstopFlag": { "$ref": "#/definitions/checkstopFlag" }
             },
 
             "required": ["ReasonCode", "Words6To9"],
@@ -139,6 +141,11 @@
             "type": "boolean"
         },
 
+        "checkstopFlag": {
+            "description": "Indicates the SRC is for a hardware checkstop.",
+            "type": "boolean"
+        },
+
         "docNotes": {
             "description": "Any notes/comments about the error. An array of strings for manual line wrapping. Optional.",
             "type": "array",