GD SMC: Only call Hold for outgoing Link

If we get a call for an incoming Link we do
not want to hold unless we want to do something with it.

Holding incoming connections can result in never Releasing

Bug: 162984360
Tag: #gd-refactor
Test: cert/run --host SecurityTest
Change-Id: I6607c79e7b3af77334fcc871c0bfe31406050978