Bluedroid: Modify PBAP vCard filtering logic.

Modify vCard filtering logic to avoid unintended removal of
vCard attribute values. During applying filters do not
remove the entries directly from original vCard, but removes
it from the concerned token, and construct the filtered vCard with
the modified tokens and return the modified vCard.

Change-Id: I348605a9742854da6bd2e2a59167641f379d88b8
CRs-Fixed: 509165