Handle PBAP response packet as raw bytes

Adjust PBAP response packet to be always handled as bytes.
Currently, it is handled as string when is read from internal data.
This causes the lack of PullvCardListing packet and the abort of
PullPhonebook transaction when multi-byte characters are contained
into corresponding contacts.
This fix will avoid the lack and the abort by writing whole packet
into the target stream as byte.

Change-Id: I17ee3ada25718cc263c9e0942f75605bd971b638