I was digging through the GiST code, and figured I'd fix up some of the

I was digging through the GiST code, and figured I'd fix up some of the
"bad smell" in that code. Stuff like function parameters that aren't
used, typos in the comments, comparison between signed and unsigned
ints, etc.

Attached is a pretty trivial patch; it compiles, but beyond that
completely untested. Unless anyone sees any problems, please apply for
7.3.

Neil Conway