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/pathgentest.cpp b/src/test/pathgentest.cpp
index 2199182..d13c82e 100644
--- a/src/test/pathgentest.cpp
+++ b/src/test/pathgentest.cpp
@@ -11,9 +11,9 @@
 
 const std::array<std::string, 3> expectedMeta =
 {
-    "path1"s,
-    "path3"s,
-    "path2"s,
+    "PATH1"s,
+    "PATH3"s,
+    "PATH2"s,
 };
 
 const std::array<std::string, 6> expectedPaths =