Add descriptor validation function & fix issues it found

Note this is in progress, I either want to move the check function somewhere else,
or convert the printf calls to something else (I imagine some kind of log function
exists?)

Jenkinsfile

@@ -45,7 +45,7 @@ pipeline {
 //                        runWaf('.', "configure clean build --target=xcoreai")
 //                        stash name: 'xua_unit_tests', includes: 'bin/*xcoreai.xe, '
                         viewEnv() {
-                          runPython("TARGET=XCORE200 pytest -n 1")
+                          runPython("TARGET=XCORE200 pytest -n1 -s")
                         }
                       }
                     }