media: cx88: Fix a null-ptr-deref bug in buffer_prepare()
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 v4.9.331 by commit c76d04d2079a4b7369ce9a0e859c0f3f2250bcc1. For more details please see the references link.