internal/pkg: optionally register binfmt

This transparently supports curing foreign exec artifacts.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/pkg/ir_test.go

@@ -39,7 +39,7 @@ func TestIRRoundtrip(t *testing.T) {
 		)},
 
 		{"exec offline", pkg.NewExec(
-			"exec-offline", nil, 0, false,
+			"exec-offline", "", nil, 0, false,
 			pkg.AbsWork,
 			[]string{"HAKUREI_TEST=1"},
 			check.MustAbs("/opt/bin/testtool"),
@@ -59,7 +59,7 @@ func TestIRRoundtrip(t *testing.T) {
 		)},
 
 		{"exec net", pkg.NewExec(
-			"exec-net",
+			"exec-net", "",
 			(*pkg.Checksum)(bytes.Repeat([]byte{0xfc}, len(pkg.Checksum{}))),
 			0, false,
 			pkg.AbsWork,