Fix voicemail count issue. - CM

Telephony checks voicemail count stored
in persist memory if SIM record returns
count zero.

Add code not to check voicemail count stored
in persist phone memory if card read success
and valid count is returned from card.

Change-Id: I69ea6e5087dd49a550bbb4b6f6721729e8cd7f15
CRs-Fixed: 655038