CVE-2022-49074

In the Linux kernel, the following vulnerability has been resolved:

irqchip/gic-v3: Fix GICR_CTLR.RWP polling

It turns out that our polling of RWP is totally wrong when checking
for it in the redistributors, as we test the *distributor* bit index,
whereas it is a different bit number in the RDs... Oopsie boo.

This is embarassing. Not only because it is wrong, but also because
it took *8 years* to notice the blunder...

Just fix the damn thing.