The default value of IEEE802154_NRF5_DELAY_TRX_ACC Kconfig option is
based on a symbol that is undefined for nRF54H20. It evaluates as empty,
which leads to compilation errors with very cryptic logs.
This commit assures that a sane value for IEEE802154_NRF5_DELAY_TRX_ACC
is selected at all times, avoiding the compilation errors.
Signed-off-by: Jędrzej Ciupis <jedrzej.ciupis@nordicsemi.no>
