CVE-2026-43072 drm/vc4: platform_get_irq_byname() returns an int

In the Linux kernel, the following vulnerability has been resolved: drm/vc4: platformgetirqbyname returns an int platformgetirqbyname will return a negative value if an error happens, so it should be checked and not just passed directly into devmrequestthreadedirq hoping all will be ok...