Some of our older buildfarm members bleat about this coding,
along the lines of

prepjointree.c:112: warning: 'get_result_relid' declared inline after being called
prepjointree.c:112: warning: previous declaration of 'get_result_relid' was here

Modern compilers will probably inline this function without being
prompted, so rather than move the function, let's just drop the
marking.