GSD-2021-1002660 ovl: fix warning in ovl_create_real()

ovl: fix warning in ovlcreatereal 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 v4.19.222 by commit 445d2dc63e5871d218f21b8f62ab29ac72f2e6b8...