{linux, linux-headers}: bump 4.{4, 9, 14, 19}.x / 5.{4, 9}.x series

Including the fix for CVE-2020-8694:
https://www.intel.com/content/www/us/en/security-center/advisory/intel-sa-00389.html



Signed-off-by: Peter Korsgaard <peter@korsgaard.com>