Bluetooth: Handle active scan case

This patch adds code to handle the active scan during interleave
scan. The interleave scan will be canceled when users start active scan,
and it will be restarted after active scan stopped.

Signed-off-by: Howard Chung <howardchung@google.com>
Reviewed-by: Alain Michaud <alainm@chromium.org>
Reviewed-by: Manish Mandlik <mmandlik@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>