Never heard of a pilot max height restriction (cabin crew - yes), with the exception of BA, who probably have a whole department devoted to administrating obscure and needless regulations dating back to it's time as a nationalised company.
Clearly though, some aircraft are considerably less comfortable for pilots of larger dimensions, but none of the operators of these smaller types have any problem with tall pilots that I have ever come across. Anybody over 6'6" may find themselves uncomfortable in the extreme, but there aren't that many lanky streaks around.
