This updates the ath10k-ct driver to the version from 2018-12-11 and
selects the ath10k-ct version based on kernel 4.19 by default.
CONFIG_ATH10K_CE was introduced between kernel 4.16 and 4.19 and is a
mandatory option.
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>