Fix shadowing of parameter in scripts

The python registries script used the variable json, which conflicts
with the "import json" module.  This commit changes the name of the
variable to json_dict, which is hopefully a more generic name:

Tested:
Ran script, observed same behavior.  Registries are out of date, but
will be updated in a later commit.

Signed-off-by: Ed Tanous <edtanous@google.com>
Change-Id: Icedc1d79ff5c9d8bfc8fe5eac96a1c6ea059272a
diff --git a/scripts/parse_registries.py b/scripts/parse_registries.py
index 155d77c..4195236 100755
--- a/scripts/parse_registries.py
+++ b/scripts/parse_registries.py
@@ -72,7 +72,7 @@
                          'resource_event_message_registry.hpp', 'resource_event'))
 
 # Remove the old files
-for file, json, namespace, url in files:
+for file, json_dict, namespace, url in files:
     try:
         os.remove(file)
     except BaseException:
@@ -82,22 +82,22 @@
         registry.write(REGISTRY_HEADER.format(namespace))
         # Parse the Registry header info
         registry.write("const Header header = {")
-        registry.write("\"{}\",".format(json["@Redfish.Copyright"]))
-        registry.write("\"{}\",".format(json["@odata.type"]))
-        registry.write("\"{}\",".format(json["Id"]))
-        registry.write("\"{}\",".format(json["Name"]))
-        registry.write("\"{}\",".format(json["Language"]))
-        registry.write("\"{}\",".format(json["Description"]))
-        registry.write("\"{}\",".format(json["RegistryPrefix"]))
-        registry.write("\"{}\",".format(json["RegistryVersion"]))
-        registry.write("\"{}\",".format(json["OwningEntity"]))
+        registry.write("\"{}\",".format(json_dict["@Redfish.Copyright"]))
+        registry.write("\"{}\",".format(json_dict["@odata.type"]))
+        registry.write("\"{}\",".format(json_dict["Id"]))
+        registry.write("\"{}\",".format(json_dict["Name"]))
+        registry.write("\"{}\",".format(json_dict["Language"]))
+        registry.write("\"{}\",".format(json_dict["Description"]))
+        registry.write("\"{}\",".format(json_dict["RegistryPrefix"]))
+        registry.write("\"{}\",".format(json_dict["RegistryVersion"]))
+        registry.write("\"{}\",".format(json_dict["OwningEntity"]))
         registry.write("};")
 
         registry.write('constexpr const char * url = "{}";\n\n'.format(url))
         # Parse each Message entry
         registry.write("constexpr std::array<MessageEntry, {}> registry = {{".format(
-            len(json["Messages"])))
-        for messageId, message in sorted(json["Messages"].items()):
+            len(json_dict["Messages"])))
+        for messageId, message in sorted(json_dict["Messages"].items()):
             registry.write("MessageEntry{")
             registry.write("\"{}\",".format(messageId))
             registry.write("{")