Bluetooth: Controller: Refactor BT_CTLR_LE_ENC implementation Refactor reused function in BT_CTLR_LE_ENC feature. Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no> (cherry picked from commit fe205a598e38549bd16620eecaef0431cfcc1b84) Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>