tee: fix compiler warning in teeshmregister()
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 v5.19.9 by commit 26e27bcb3d3d075c1e8bfd75927a8b29f31f6e3a, it was introduced in version v5.19.3 by commit 58c008d4d398f792ca67f35650610864725518fd. For more details please see the references link.