src/libpcp/src/getdate.y: for pure parser use a more modern declaration
src/libpcp/src/getdate.y: for pure parser use a more modern declaration

Compilation warning from bison spotted on OpenIndiana.

adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp