Bluetooth: hci_core: Move all debugfs handling to hci_debugfs.c

This moves hci_debugfs_create_basic to hci_debugfs.c which is where all
the others debugfs entries are handled.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>