bitbake: build.py: Logging of None was losing the logs so force this to stdout so we can see function execution failures

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/build.py

@@ -233,7 +233,7 @@ def exec_func_shell(function, d, runfile, cwd=None):
     if logger.getEffectiveLevel() <= logging.DEBUG:
         logfile = LogTee(logger, sys.stdout)
     else:
-        logfile = None
+        logfile = sys.stdout
 
     try:
         bb.process.run(cmd, env=env, cwd=cwd, shell=False, stdin=NULL,