Adds Path to platform.File and refactors tests (#1431)

Signed-off-by: Adrian Cole <adrian@tetrate.io>
Signed-off-by: Edoardo Vacchi <evacchi@users.noreply.github.com>
Co-authored-by: Edoardo Vacchi <evacchi@users.noreply.github.com>

internal/sysfs/readfs.go

@@ -67,7 +67,7 @@ func (r *readFS) OpenFile(path string, flag int, perm fs.FileMode) (platform.Fil
 	if errno != 0 {
 		return nil, errno
 	}
-	return &platform.DefaultFile{F: maskForReads(f.File())}, 0
+	return platform.NewFsFile(path, maskForReads(f.File())), 0
 }
 
 // maskForReads masks the file with read-only interfaces used by wazero.