fix words misspell

Signed-off-by: Michael Wan <zirenwan@gmail.com>

container_linux_test.go

@@ -375,12 +375,12 @@ type directIO struct {
 	cio.DirectIO
 }
 
-// ioCreate returns IO avaliable for use with task creation
+// ioCreate returns IO available for use with task creation
 func (f *directIO) IOCreate(id string) (cio.IO, error) {
 	return f, nil
 }
 
-// ioAttach returns IO avaliable for use with task attachment
+// ioAttach returns IO available for use with task attachment
 func (f *directIO) IOAttach(set *cio.FIFOSet) (cio.IO, error) {
 	return f, nil
 }