blk-throttle: prevent overflow while calculating wait time

blk-throttle: prevent overflow while calculating wait time

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 v5.10.150 by commit 19c010ae44f0ce52b5436080492a61a092ee0cf4. For more details please see the references link.