btsnoop: Fix btsnoop_net runs unexpected

By default, btsnoop_net was disabled using "BT_NET_DEBUG" macro.
But, it enabled actually and manages socket connection for sending
btsnoop logs. The reason was, TRUE/FALSE macro were not defined.
This fix including "bt_types.h" to work macro properly.

Test: Turn on btsnoop logging and observe btsnoop_net runs or not.

Signed-off-by: KimJeongYeon <jeongyeon.kim@samsung.com>