hwrng: cavium - fix NULL but dereferenced coccicheck error
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 v5.17.2 by commit e47b12f9415169eceda6770fcf45802e0c8d2a66. For more details please see the references link.