CVE-2022-50022 drivers:md:fix a potential use-after-free bug

In the Linux kernel, the following vulnerability has been resolved: drivers:md:fix a potential use-after-free bug In line 2884, "raid5releasestripesh;" drops the reference to sh and may cause sh to be released. However, sh is subsequently used in lines 2886 "if sh-batchhead && sh != sh-batchhead"...