Comment 15 for bug 1923162

@sil2100 sorry - that's my fault for skimming this (and the breaks: bit too -- that's actually not necessary as the backport re-instates the postinst installing the binaries to the boot partition; the breaks was there as later releases ditched the postinst and passed the responsibility for copying u-boot to flash-kernel). I'll work with jawn-smith to get this fixed up.