pdmgen: Require uppercase meta keys

journald ignores lowercase metadata keys so require them
to be uppercase.  Abort the config file parse when lowercase
keys are found.

Change-Id: Icffffdc6680b4d305329c3395f8e2fda6210964f
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/src/test/yaml/callbackgentest/two.yaml b/src/test/yaml/callbackgentest/two.yaml
index 6037f43..1f61e3b 100644
--- a/src/test/yaml/callbackgentest/two.yaml
+++ b/src/test/yaml/callbackgentest/two.yaml
@@ -4,9 +4,9 @@
   class: group
   group: path
   members:
-    - meta: path
+    - meta: PATH
       path: /xyz/openbmc_project/testing/inst4
-    - meta: path
+    - meta: PATH
       path: /xyz/openbmc_project/testing/inst6
 
 - name: test property group 1
@@ -15,7 +15,7 @@
   type: string
   members:
     - interface: xyz.openbmc_project.Sensor.Iface3
-      meta: property
+      meta: PROPERTY
       property: Value2
 
 - name: test journal callback 1