Unify `getIpcMemHandle()` and `getIpcMemHandles()` and fix the issue of
missing IPC handles registration while reducing copy-pasted code.
Also replace `boHandle` with `boHandleWrapper` to leverage `refCount`
properly and avoid double-free.
Related-To: NEO-8904
Signed-off-by: Maciej Bielski <maciej.bielski@intel.com>