Use new kernel's spidev's word_delay_usecs

This is quite bleeding edge, corresponding to my kernel branch
cesnet/2018-03-07--spi-01. Note that one has to use the `--no-renames`
option when creating such a patch...

Also pull in latest cla-sysrepo and netconf-cli.

[1] https://gerrit.cesnet.cz/plugins/gitiles/github/buildroot/buildroot/+/85f11d08c387c200dbb59a8559f2ba62376689bf

Change-Id: I12575b56a0bfbf8e1fe5e9e5818cf1ba1ab3aca4
Depends-on: https://patchwork.kernel.org/project/spi-devel-general/list/?series=88941
Depends-on: https://cesnet-gerrit-czechlight/c/CzechLight/cla-sysrepo/+/1555
Depends-on: https://gerrit.cesnet.cz/c/CzechLight/cla-sysrepo/+/1555
diff --git a/.zuul.yaml b/.zuul.yaml
index 5283b5e..d60b5d3 100644
--- a/.zuul.yaml
+++ b/.zuul.yaml
@@ -14,7 +14,7 @@
       - github/sysrepo/sysrepo
       - github/CESNET/libnetconf2
       - github/CESNET/Netopeer2
-      - github/philsquared/Catch
+      - github/onqtam/doctest
       - github/docopt/docopt.cpp
       - github/gabime/spdlog
       - github/rollbear/trompeloeil