Kernel prepatch 5.19-rc7

We obviously had that whole "Retbleed" thing, and it does show up in both the diffstat and the shortlog, and rc7 is definitely bigger than usual. And also as usual, when we've had one of those embargoed hw issues pending, the patches didn't get the open development, and then as a result missed all the usual sanity checking by all the automation build and test infrastructure we have. So no surprise - there's been various small fixup patches afterwards too for some corner cases.

That said, last week there were two other development trees that independently also asked for an extension, so 5.19 will be one of those releases that have an additional rc8 next weekend before the final release.