Src/Dst SMR should be sent for simple Dst prefix too

When a Src/Dst mapping is updated for EID B|A where B is the source prefix and A is the destination prefix in the policy, an SMR is sent to EID B|A. However, some data plane elements may have requested the mapping as a simple Map-Request for A, not B|A and don't understand LCAF 12. We still want them to get the updated policy. So the SMR mechanism should send the SMR for A instead of B|A (or both?)