hack/make/.go-autogen: fix "generated code" comment not in correct format

As described in https://golang.org/s/generatedcode, Go has
a formalized format that should be used to indicate that a
file is generated.

Matching that format helps linters to skip generated files;

From https://golang.org/s/generatedcode (https://github.com/golang/go/issues/13560#issuecomment-288457920);

> Generated files are marked by a line of text that matches the regular expression, in Go syntax:
>
> ^// Code generated .* DO NOT EDIT\.$
>
> The `.*` means the tool can put whatever folderol it wants in there, but the comment
> must be a single line and must start with `Code generated` and end with `DO NOT EDIT.`,
> with a period.
>
> The text may appear anywhere in the file.

This patch updates the autogenerated code to match that format.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

hack/make/.go-autogen

@@ -24,7 +24,7 @@ const (
 	DefaultProductLicense string = "${DEFAULT_PRODUCT_LICENSE}"
 )
 
-// AUTOGENERATED FILE; see /go/src/github.com/docker/docker/hack/make/.go-autogen
+// Code generated by hack/make/.go-autogen. DO NOT EDIT.
 DVEOF
 
 cat > dockerversion/version_autogen_unix.go <<DVEOF
@@ -39,7 +39,7 @@ const (
 	InitCommitID string = "${TINI_COMMIT}"
 )
 
-// AUTOGENERATED FILE; see /go/src/github.com/docker/docker/hack/make/.go-autogen
+// Code generated by hack/make/.go-autogen. DO NOT EDIT.
 DVEOF
 
 # Compile the Windows resources into the sources