component/nxdtest: upgrade nxdtest to latest version

This especially brings support for systems where 'model name' is not
present in /proc/cpuinfo

component/nxdtest/buildout.cfg

@@ -31,6 +31,6 @@ depends = ${python-prctl:egg}
 [nxdtest-repository]
 recipe  = slapos.recipe.build:gitclone
 repository = https://lab.nexedi.com/nexedi/nxdtest.git
-revision = 56e52da6
+revision = 19c7022c
 location = ${buildout:parts-directory}/nxdtest
 git-executable = ${git:location}/bin/git