Bluetooth: controller: Fix PPIs use for nRF52805 SoC

Fix regression in PPIs use for nRF52805 SoC, which has
fewer of them. And the regression was introduced in
commit e603b9d5 ("Bluetooth: controller: Adjust PPI
used for nRF51x and nRF52x").

Fixes #35204.

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