shared/hfp: Fix for invalid string copy
shared/hfp: Fix for invalid string copy

This part of code handles case when data in ring buffer are wrapped.
In that case str is not a string so we shall not use asprintf but
memcpy

pstglia/external-bluetooth-bluez,silent-snowman/bluez,mapfau/bluez,pkarasev3/bluez,pkarasev3/bluez,ComputeCycles/bluez,pstglia/external-bluetooth-bluez,ComputeCycles/bluez,silent-snowman/bluez,pstglia/external-bluetooth-bluez,pstglia/external-bluetooth-bluez,mapfau/bluez,silent-snowman/bluez,mapfau/bluez,pkarasev3/bluez,mapfau/bluez,ComputeCycles/bluez,silent-snowman/bluez,ComputeCycles/bluez,pkarasev3/bluez