At creation, calls were badly tracked into call map due to wrong
key used (was the account type string).
Changed for the LINK_TYPE (it's the same for Ring and SIP call).

This fix a bug when getCall<SIPCall> is used for fetching
Ring AND SIP calls (was return only SIP, never RING calls).

Issue: #79075
Change-Id: I50428ce00d16cafdf1d33e39acc59a452d0c312a