iio: Use per-device lockdep class for mlock
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 v6.0.3 by commit a47cd740b16a07f415286b39bd93058797cf9b39, it was introduced in version v4.10 by commit 67e17300dc1d76091d2d513d6aa57e50af2c9648. For more details please see the references link.