PBAP: Remove initialisation of Missed calls number

Thic change will remove initialisation of Missed calls number
at the time of connection as NewMissedCall number indicates the
number of missed calls that have been received on the PSE since
the last PullPhoneBook request on the mch folder, at the point
of the request.

Change-Id: I5f769011a34cfe8e7225fca646a58451639dcfa5