Bluetooth: Controller: Make PHY check in conn mode Kconf dependent

Constant Tone Extension may not be transmittied with PHY CODED.
There were check to avoid situation that controller tries to
transmit or receive CTE when PHY is set to CODED.
These check were not conditionally compilated, hence when
PHY Update feature is disabled code did build.

The commit fixes the issue.

Signed-off-by: Piotr Pryga <piotr.pryga@nordicsemi.no>