ipaddr: Exempt from all lint rules

The code in this package is all snapshot from the Go codebase in older
versions, inlined here to allow OpenTofu's cidr-calculation-related
functions to preserve their original behavior despite upstream changing
the parsing rules in a breaking way.

This code is intentionally modified as little as possible from the upstream
code it was derived from. We are imposing on ourselves considerably
stricter style conventions than the Go project follows and so we need
to disable various linters for this package to allow this code to remain
written in the Go idiomatic style, rather than in OpenTofu's stricter
local style.

In particular, we've chosen to prohibit ourselves from using named return
values or package-global variables, despite those both being typical in the
standard library and in other codebases.

Signed-off-by: Martin Atkins <mart@degeneration.co.uk>

internal/ipaddr/ip.go

@@ -10,6 +10,7 @@
 // This library accepts either size of byte slice but always
 // returns 16-byte addresses.
 
+//nolint:cyclop,funlen,gochecknoglobals,gocritic,nonamedreturns,mnd // This file is copied from the Go codebase and intended to remain close to the original in case we need to backport changes.
 package ipaddr
 
 import (

internal/ipaddr/ip_test.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//nolint:gochecknoglobals,gocritic,govet // This file is copied from the Go codebase and intended to remain close to the original in case we need to backport changes.
 package ipaddr
 
 import (

internal/ipaddr/parse.go

@@ -5,6 +5,7 @@
 // Simple file i/o and string manipulation, to avoid
 // depending on strconv and bufio and strings.
 
+//nolint:nonamedreturns,mnd // This file is copied from the Go codebase and intended to remain close to the original in case we need to backport changes.
 package ipaddr
 
 // Bigger than we need, not too big to worry about overflow