The standard uses 80+80 and 80p80 but nowhere 80_80.
Swicth the latter to 80P80 for all the macros and comments refering
to #defined flags which I could find.
The only place we leave as 80p80 is the ifconfig command line arguments
as we spell them all in lower case.
Ideally we would use 80+80 for anything to the user and 80P80 for anything
internal but let us not confuse parsers and hence avoid the '+' in
either case.

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