Bluetooth: AVRCP: Add SDP attributes.

This patch add SDP records for both CT and TG role.

The SDP attribute would be registered according to the configuration.

OBEX and Browsing commands are optional and yet not supported.

SDP registration is implemented at AVRCP level to simplify the
workload of the upper layer. We assume the App can have limited
knowledge on SDP structures.

Signed-off-by: Zihao Gao <gaozihao@xiaomi.com>