amt: fix possible memory leak in amt_rcv()
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 v5.18.4 by commit 4b8032d39b276c52db57ff834c300405b9da2691, it was introduced in version v5.16 by commit cbc21dc1cfe949e37b2a54c71511579f1899e8d4. For more details please see the references link.