Issue 128554727: UE fail to unhold call when user swap active/hold call.

[root cause  ]"onHold" state of ImsCall is N  but  the session is held
[changes     ]Change the mHold when callSessionHeld
[issue address]https://partnerissuetracker.corp.google.com/u/0/issues/128554727

Change-Id: Iaa707ceb1713f563844f4227d76435db41fa0884