Bluetooth: controller: Fix Code PHY update support dependency

Fix the regression introduced as part of
commit 57d94118 ("bluetooth: kconfig: disable some
options for openisa/RV32M1").

Also, prior to PR that introduced this regression, the Coded
PHY support selection was incorrectly depending on PHY update
support Kconfig BT_PHY_UPDATE. This was already fixed as part
the previous PR.

Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>