Is there some harm is having them set in the .dts?
I can see 'linux,boot-cpu' may vary on a SMP, but the majority
of .dts's are for uniproc's
The way this is handled in the OF binding, only multi-processor
systems are required to explicitly state their boot CPU (in
/chosen/cpu). It's quite silly to require this for single
CPU systems.
Segher