fix for onefile FITSint, FITSuint

fix for onefile FITSint, FITSuint

I assumed that the complaint about macro refinition was for the two
in alloc.c replacing two from hack.h from another file, but it could
be that those being defined by alloc.c were interferring with the
regular hack.h ones.  alloc.c doesn't need them, and was also skipping
an opportunity to use one of them.