Synchronize the RPL thread updating the RPL netstats with the RPL
shell command reading it by disabling IRQs. This will prevent printing
corrupted data on non-32bit platforms as well as printing inconsistent
data (e.g. TX count of old state in conjunction with TX bytes of new
state) for all platforms.
Co-authored-by: Martine Lenders <mail@martine-lenders.eu>
There is a repeating pattern in the struct that is split out into a
subtype in this commit. This makes handling the data easier, as now
done in the print routine.
