Yocto 2.3

Move OpenBMC to Yocto 2.3(pyro).

Tested: Built and verified Witherspoon and Palmetto images
Change-Id: I50744030e771f4850afc2a93a10d3507e76d36bc
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
Resolves: openbmc/openbmc#2461
diff --git a/import-layers/yocto-poky/bitbake/lib/bb/process.py b/import-layers/yocto-poky/bitbake/lib/bb/process.py
index c62d7bc..a4a5599 100644
--- a/import-layers/yocto-poky/bitbake/lib/bb/process.py
+++ b/import-layers/yocto-poky/bitbake/lib/bb/process.py
@@ -162,9 +162,9 @@
         stdout, stderr = _logged_communicate(pipe, log, input, extrafiles)
     else:
         stdout, stderr = pipe.communicate(input)
-        if stdout:
+        if not stdout is None:
             stdout = stdout.decode("utf-8")
-        if stderr:
+        if not stderr is None:
             stderr = stderr.decode("utf-8")
 
     if pipe.returncode != 0: