Avoid copy

cppcheck warns that this is a copy, so fix it.

Tested: cppcheck no longer warns on this line.  Unfortunately, virtual
media does not have a backend, so this is dead code.  No way to test at
this point.

Signed-off-by: Ed Tanous <edtanous@google.com>
Change-Id: I1e98ca63ee346ad683844e5637a173f64286102a
diff --git a/redfish-core/lib/virtual_media.hpp b/redfish-core/lib/virtual_media.hpp
index 402cbbd..f287cb2 100644
--- a/redfish-core/lib/virtual_media.hpp
+++ b/redfish-core/lib/virtual_media.hpp
@@ -561,7 +561,7 @@
         return credentials.password();
     }
 
-    SecureBuffer pack(FormatterFunc formatter)
+    SecureBuffer pack(FormatterFunc* formatter)
     {
         SecureBuffer packed{new Buffer{}};
         if (formatter != nullptr)