bluetooth: controller: Handle non-priority events correctly

In certain cases the response to a command can come in the form of a
non-priority event. This is the case of LE Create Connection Cancel,
which generates a Command Complete and then an LE (Enh) Connection
Complete. Take this case (and other future ones) into account by calling
the correct Host recv function.

Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>