Revert "dm-crypt: Add IV generation templates"

hulk inclusion
category: bugfix
bugzilla: 31797
CVE: NA

--------------------------------

We come across a KASAN double-free issue which seems to be related with
this patch. Let's revert this patch for now.

This reverts commit 3449c349585d560f37db2fb938347eb37e78bcae.

Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Reviewed-by: ZhangXiaoxu <zhangxiaoxu5@huawei.com>
Reviewed-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>