give_way and stop direction warnings should also check for prefixed variants.

[WKobes]

• item number: 2090
• class number: 4

Currently, the give_way and stop nodes on highways are required to have an direction tag. However, this warning is also raised when the give_way:direction or stop:direction tags are used.

These are valid according to the wiki:
https://wiki.openstreetmap.org/wiki/Key:give_way:direction
https://wiki.openstreetmap.org/wiki/Key:stop:direction