Bluetooth: Move manufacturer, hci_ver and hci_rev into hci_core.c

Move the debugfs entries for manufacturer, hci_ver and hci_rev into
hci_core.c and use the new helpers for static entries that will not
change at runtime. Once passed the setup procedure, they will stay
fixed.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>