CVE-2024-56781 powerpc/prom_init: Fixup missing powermac #size-cells

In the Linux kernel, the following vulnerability has been resolved: powerpc/prominit: Fixup missing powermac size-cells On some powermacs escc nodes are missing size-cells properties, which is deprecated and now triggers a warning at boot since commit 045b14ca5c36 "of: WARN on deprecated...