mm/mempolicy: fix uninit-value in mpolrebindpolicy()
This is an automated ID intended to aid in discovery of potential security vulnerabilities. The actual impact and attack plausibility have not yet been proven. This ID is fixed in Linux Kernel version v4.19.254 by commit 13d51565cec1aa432a6ab363edc2bbc53c6f49cb. For more details please see the references link.