Bluetooth: Fix HCI init for BlueFRITZ! devices

None of the BlueFRITZ! devices with manufacurer ID 31 (AVM Berlin)
support HCI_Read_Local_Supported_Commands. It is safe to use the
manufacturer ID (instead of e.g. a USB ID specific quirk) because the
company never created any newer controllers.

< HCI Command: Read Local Supported Comm.. (0x04|0x0002) plen 0 [hci0] 0.210014
> HCI Event: Command Status (0x0f) plen 4 [hci0] 0.217361
      Read Local Supported Commands (0x04|0x0002) ncmd 1
        Status: Unknown HCI Command (0x01)

Reported-by: Jörg Esser <jackfritt@boh.de>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Tested-by: Jörg Esser <jackfritt@boh.de>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>