mod: Fix tredoe/osutil library version

The Go modules for this library are broken[1] due to the missing v1.1.0
tag. As a result, `go get -u` fails without this replace with the
following error:

    $ go get -u
    [...]
    go: reading github.com/tredoe/osutil/go.mod at revision v1.1.0: unknown revision v1.1.0
    $ echo $?
    1

[1]: tredoe/osutil#15

Signed-off-by: Joe Groocock <me@frebib.net>

go.mod

@@ -167,3 +167,6 @@ require (
 replace github.com/u-root/u-root v7.0.0+incompatible => github.com/u-root/u-root v1.0.1
 
 replace github.com/insomniacslk/dhcp => github.com/insomniacslk/dhcp v0.0.0-20221001123530-5308ebe5334c
+
+// https://github.com/tredoe/osutil/issues/15
+replace github.com/tredoe/osutil => github.com/tredoe/osutil v2.0.0-rc.16+incompatible