If the client socket is closed, asyncio.StreamReader.readline() will
return an empty bytes object, not None.
This prevents multiple tracebacks being logged by bitbake-hashserv each
time bitbake is started and performs a connection check.
(Bitbake rev: 2d07f252704dff7747fa1f9adf223a452806717f)
Signed-off-by: Justin Bronder <jsbronder@cold-front.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>