Bluetooth: Add option to use heuristics for VS HCI detection

On targets where non-Zephyr controllers are likely, such as qemu, it
may be harmful to try to issue any of the vendor HCI commands, since
non-Zephyr controllers may interpret them in completely different
ways.

Introduce a Kconfig option that, when enabled, uses some simple
heuristics (HCI version & lack of public address) to try to guess in
advance whether the Zephyr HCI vendor extensions are supported or not.
The new option is available for any host-only configuration and is
enabled by default for the qemu targets.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2 files changed