std,cmd: go fix -any std cmd

std,cmd: go fix -any std cmd

This change mechanically replaces all occurrences of interface{}
by 'any' (where deemed safe by the 'any' modernizer) throughout
std and cmd, minus their vendor trees.

Since this fix is relatively numerous, it gets its own CL.

Also, 'go generate go/types'.

Change-Id: I14a6b52856c3291c1d27935409bca8d5fd4242a2
Reviewed-on: https://go-review.googlesource.com/c/go/+/719702
Commit-Queue: Alan Donovan <adonovan@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Auto-Submit: Alan Donovan <adonovan@google.com>