Kernel prepatch 5.11-rc5

The 5.11-rc5 kernel prepatch is out fortesting. "Nothing particularly stands out. We had a couple of splice()regressions that came in during the previous release as part of the'get rid of set_fs()' development, but they were for odd cases thatmost people would never notice. I think it's just that 5.10 is nowgetting more widely deployed so people see the fallout from thatrather fundamental change in the last release."