Really we need to fix the inheritance to make BpfMapRO the parent class of BpfMap: but that's a far more difficult thing to do, so in the short term we punt like this. This makes BpfMapRO a little bit more usable, and allows a slow transition across the codebase... Test: TreeHugger Signed-off-by: Maciej Żenczykowski <maze@google.com> Change-Id: I1c5112db70e9e523c113cba536fbe19422b4d3f3