Remove a couple of unnecessary var declarations, an unused sort.Sort
type, and simplify a range by using the two-name variant.

Change-Id: Ia251f634db0bfbe8b1d553b8659272ddbd13b2c3
Reviewed-on: https://go-review.googlesource.com/102336
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>