Kernel prepatch 5.4-rc8

As expected, 5.4-rc8 was released onNovember 17 rather than the final 5.4 release."I'm not entirely sure we need an rc8, because last week was prettycalm despite the Intel hw workarounds landing. So I considered justmaking a final 5.4 and be done with it, but decided that there's noreal downside to just doing the rc8 after having a release cycle thattook a while to calm down."