Some old hci controllers do not accept any mask so leave the
default mask on for these devices.

< HCI Command: Set Event Mask (0x03|0x0001) plen 8
    Mask: 0xfffffbff00000000
> HCI Event: Command Complete (0x0e) plen 4
    Set Event Mask (0x03|0x0001) ncmd 1
    status 0x12
    Error: Invalid HCI Command Parameters
Signed-off-by: Ville Tervo <ville.tervo@nokia.com>
Tested-by: Corey Boyle <corey@kansanian.com>
Tested-by: Ed Tomlinson <edt@aei.ca>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>