Enable 3 member function checks

The only changes were to make some functions static, which is
essentially no-op.

Changes were done by the robot.

Tested: Unit tests pass, changes no-op

Signed-off-by: Ed Tanous <edtanous@google.com>
Change-Id: Id84ca2bee6f237877ba2900b2cbe4679b38a91dc
diff --git a/redfish-core/include/gzfile.hpp b/redfish-core/include/gzfile.hpp
index 567741d..696b13c 100644
--- a/redfish-core/include/gzfile.hpp
+++ b/redfish-core/include/gzfile.hpp
@@ -38,7 +38,7 @@
     std::string lastDelimiter;
     size_t totalFilesSize = 0;
 
-    void printErrorMessage(gzFile logStream)
+    static void printErrorMessage(gzFile logStream)
     {
         int errNum = 0;
         const char* errMsg = gzerror(logStream, &errNum);