mISDN: fix misuse of put_device() in mISDN_register_device()
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 v5.4.225 by commit 83672c1b83d107b0d4fe0accf1bf64d8988398e6, it was introduced in version v5.4.224 by commit 2ff6b669523d3b3d253a044fa9636a67d0694995. For more details please see the references link.