PEL: Refactor the test data factory

This commit has no functional changes, it just does some things
to make the PEL data creator for testcases, pelDataFactory(), be
more manageable:

- Change to return a plain vector instead of a unique_ptr<vector>.
- Keeps the data for each section in separate vectors and then
  either returns those as-is or combines them into a PEL.
- Change the TestPelType enum to TestPELType to match the style guide.
- Have pelDataFactory provide the SRC section instead of srcDataFactory.

Signed-off-by: Matt Spinler <spinler@us.ibm.com>
Change-Id: I4770aa6a8169e89b6b8f685a9994d845c9e93cfe
diff --git a/test/openpower-pels/pel_manager_test.cpp b/test/openpower-pels/pel_manager_test.cpp
index 61fbedd..9014dd8 100644
--- a/test/openpower-pels/pel_manager_test.cpp
+++ b/test/openpower-pels/pel_manager_test.cpp
@@ -34,11 +34,11 @@
 
     // Create a PEL, write it to a file, and pass that filename into
     // the create function.
-    auto data = pelDataFactory(TestPelType::pelSimple);
+    auto data = pelDataFactory(TestPELType::pelSimple);
 
     fs::path pelFilename = makeTempDir() / "rawpel";
     std::ofstream pelFile{pelFilename};
-    pelFile.write(reinterpret_cast<const char*>(data->data()), data->size());
+    pelFile.write(reinterpret_cast<const char*>(data.data()), data.size());
     pelFile.close();
 
     std::string adItem = "RAWPEL=" + pelFilename.string();