fw/rt_config: Fix validation checks
fw/rt_config: Fix validation checks

Remove unnecessary validation checks and fix remaining so they don't fail
under certain combinations of parameters.

ARM-software/workload-automation,ARM-software/workload-automation,lisatn/workload-automation,setrofim/workload-automation,lisatn/workload-automation,setrofim/workload-automation,lisatn/workload-automation,ARM-software/workload-automation,setrofim/workload-automation,ARM-software/workload-automation,lisatn/workload-automation,setrofim/workload-automation