cmd/gorename: delete

Fixes golang/go#69360

Change-Id: Ifea5e45eae670c45861fbc1f09ebe2872260b2e0
Reviewed-on: https://go-review.googlesource.com/c/tools/+/614675
Reviewed-by: Robert Findley <[email protected]>
Auto-Submit: Alan Donovan <[email protected]>
LUCI-TryBot-Result: Go LUCI <[email protected]>

Author: adonovan