check: move from container

This package is not container specific, and widely used across the project.

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

container/initproc.go

@@ -5,7 +5,7 @@ import (
 	"fmt"
 	. "syscall"
 
-	"hakurei.app/container/check"
+	"hakurei.app/check"
 )
 
 func init() { gob.Register(new(MountProcOp)) }