Bluetooth: Set name_state to unknown when entry name is empty

commit c3e7c0d90b14a3e7ac091d24cef09efb516d587b upstream.

When the name of the given entry is empty , the state needs to be
updated accordingly.

Signed-off-by: Ram Malovany <ramm@ti.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>