PEL: Fix more cppcheck warnings

This is the second of two commits to fix most of the cppcheck warnings
in the PEL code.  It doesn't fix all of them because some are false
positives and some are just suggestions.

It's broken up into two commits to make them smaller.

Signed-off-by: Matt Spinler <spinler@us.ibm.com>
Change-Id: Id9f462386df85fd25d09529d6b410115ff4ccba8
diff --git a/test/openpower-pels/fru_identity_test.cpp b/test/openpower-pels/fru_identity_test.cpp
index 28a8e98..24ac5fe 100644
--- a/test/openpower-pels/fru_identity_test.cpp
+++ b/test/openpower-pels/fru_identity_test.cpp
@@ -89,7 +89,7 @@
     EXPECT_THROW(FRUIdentity fru{stream}, std::out_of_range);
 }
 
-void testHWCallout(const std::string& pn, const std::string ccin,
+void testHWCallout(const std::string& pn, const std::string& ccin,
                    const std::string& sn, const std::string& expectedPN,
                    const std::string& expectedCCIN,
                    const std::string& expectedSN)