Send tempest.log to the packstack log directory

Otherwise it gets written to /var/lib/tempest/tempest.log which is
not where logs should be kept.

Change-Id: I5ee2c30f93e0bf53c0a450dace891ae46307157b

packstack/installer/run_setup.py

@@ -968,6 +968,7 @@ def main():
 
         controller.CONF['DEFAULT_EXEC_TIMEOUT'] = options.timeout
         controller.CONF['DRY_RUN'] = options.dry_run
+        controller.CONF['DIR_LOG'] = basedefs.DIR_LOG
 
         # If --gen-answer-file was supplied, do not run main
         if options.gen_answer_file: