mtd: Fix device name leak when register device failed in addmtddevice()
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 v5.15.86 by commit 71212d73184845c944ef1b43f092e643e5bde003, it was introduced in version v2.6.30 by commit 1f24b5a8ecbb2a3c7080f418974d40e3ffedb221. For more details please see the references link.