powerpc/64: Fix the definition of the fixmap area
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 v5.12.4 by commit a84df7c80bdac598d6ac9268ae578da6928883e8, it was introduced in version v5.5 by commit 265c3491c4bc8d40587996d6ee2f447a7ccfb4f3. For more details please see the references link.