android/pan: Register PANU sdp record while registering PAN
android/pan: Register PANU sdp record while registering PAN

This patch adds support for registering and unregistering PANU sdp
record.
It's related with PTS test case: TC_SDP_PANU_BV_01_C, which requires
PANU sdp record to be registered.

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