Added null check in modules/ca/src/client/udpiiu.cpp to prevent possib…
Created by: karlvestin
…le dereferencing of null pointer. Flagged as error by Codacy static code analysis.
Codacy link: https://app.codacy.com/gh/epics-base/epics-base/file/42103575495/issues/source?bid=16430872&fileBranchId=16430872#l950 Launchpad bug: https://bugs.launchpad.net/epics-base/+bug/1862916