container/seccomp: remove export pipe

This was only useful when wrapping bwrap.

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

container/seccomp/hash_test.go

@@ -1,6 +1,7 @@
 package seccomp_test
 
 import (
+	"crypto/sha512"
 	"encoding/hex"
 
 	"hakurei.app/container/bits"
@@ -12,18 +13,18 @@ type (
 		seccomp.ExportFlag
 		bits.FilterPreset
 	}
-	bpfLookup map[bpfPreset][]byte
+	bpfLookup map[bpfPreset][sha512.Size]byte
 )
 
-func toHash(s string) []byte {
-	if len(s) != 128 {
+func toHash(s string) [sha512.Size]byte {
+	if len(s) != sha512.Size*2 {
 		panic("bad sha512 string length")
 	}
 	if v, err := hex.DecodeString(s); err != nil {
 		panic(err.Error())
-	} else if len(v) != 64 {
+	} else if len(v) != sha512.Size {
 		panic("unreachable")
 	} else {
-		return v
+		return ([sha512.Size]byte)(v)
 	}
 }