os: support Stat and LStat for CON device on Windows

os: support Stat and LStat for CON device on Windows

\\.\con and CON need to be opened with GENERIC_READ access, else
CreateFile will fail with ERROR_INVALID_PARAMETER.

Special-case ERROR_INVALID_PARAMETER in os.[L]Stat so it retries with
GENERIC_READ access.

Fixes #34900.

Change-Id: I5010e736d0189c8ada4fc0eca98d71a438c41426
Reviewed-on: https://go-review.googlesource.com/c/go/+/560755
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
Reviewed-by: David Chase <drchase@google.com>