cmd/bent: yank initialization from main function

Non-functional change, just cleaning things up.

Change-Id: I266fa7adf4a34e941c222423377b963c1ceaa8e0
Reviewed-on: https://go-review.googlesource.com/c/benchmarks/+/290990
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Jeremy Faller <jeremy@golang.org>
Run-TryBot: Jeremy Faller <jeremy@golang.org>
Reviewed-by: David Chase <drchase@google.com>
1 file changed