[auto-upgrade-helper] bitbake: consider both stdout and stderr when checking or logging output

diff --git a/modules/buildhistory.py b/modules/buildhistory.py
index 6649023..e0f7191 100644
--- a/modules/buildhistory.py
+++ b/modules/buildhistory.py
@@ -43,7 +43,7 @@  class BuildHistory(object):
             try:
                 self.bb.complete(self.pn, machine)
             except Error as e:
-                for line in e.stdout.split("\n"):
+                for line in e.stdout.split("\n") + e.stderr.split("\n"):
                     # version going backwards is not a real error
                     if re.match(".* went backwards which would break package feeds .*", line):
                         break
diff --git a/modules/steps.py b/modules/steps.py
index 811b88d..bde72db 100644
--- a/modules/steps.py
+++ b/modules/steps.py
@@ -107,8 +107,8 @@  def _compile(bb, pkg, machine, workdir):
             bb.complete(pkg, machine)
         except Error as e:
             with open("{}/bitbake-output-{}.txt".format(workdir, machine), 'w') as f:
-                f.write(e.stdout)
-            for line in e.stdout.split("\n"):
+                f.write(e.stdout + e.stderr)
+            for line in e.stdout.split("\n") + e.stderr.split("\n"):
                 # version going backwards is not a real error
                 if re.match(".* went backwards which would break package feeds .*", line):
                     break
diff --git a/modules/testimage.py b/modules/testimage.py
index 4272c84..0fc1adb 100644
--- a/modules/testimage.py
+++ b/modules/testimage.py
@@ -85,14 +85,14 @@  class TestImage():
             bitbake_create_output = self.bb.complete(image, machine)
         except Error as e:
             I( "   building the testimage failed! Collecting logs...")
-            bitbake_create_output = e.stdout
+            bitbake_create_output = e.stdout + e.stderr
         else:
             I( "   running %s/testimage for %s ..." % (image, machine))
             try:
                 bitbake_run_output = self.bb.complete("%s -c testimage" % image, machine)
             except Error as e:
                 I( "   running the testimage failed! Collecting logs...")
-                bitbake_run_output = e.stdout
+                bitbake_run_output = e.stdout + e.stderr
 
         if bitbake_create_output:
             with open(os.path.join(self.logdir, "bitbake-create-testimage.log"), 'w') as f:
diff --git a/modules/utils/bitbake.py b/modules/utils/bitbake.py
index 4835ca6..a5fc6fa 100644
--- a/modules/utils/bitbake.py
+++ b/modules/utils/bitbake.py
@@ -73,7 +73,7 @@  class Bitbake(object):
 
             if self.log_dir is not None and os.path.exists(self.log_dir):
                 with open(os.path.join(self.log_dir, BITBAKE_ERROR_LOG), "a+") as log:
-                    log.write(e.stdout)
+                    log.write(e.stdout + e.stderr)
 
             raise Error("\'" + cmd + "\' failed", e.stdout, e.stderr)
 
diff --git a/upgrade-helper.py b/upgrade-helper.py
index eb3935e..ecdabb0 100755
--- a/upgrade-helper.py
+++ b/upgrade-helper.py
@@ -153,7 +153,7 @@  class Updater(object):
         except EmptyEnvError as e:
             import traceback
             E( " %s\n%s" % (e.message, traceback.format_exc()))
-            E( " Bitbake output:\n%s" % (e.stdout))
+            E( " Bitbake output:\n%s" % (e.stdout + e.stderr))
             exit(1)
 
         self._set_options()
@@ -459,7 +459,7 @@  class Updater(object):
                     E(" Can't build gcc-runtime for %s." % machine)
 
                     if isinstance(e, Error):
-                        E(e.stdout)
+                        E(e.stdout + e.stderr)
                     else:
                         import traceback
                         traceback.print_exc(file=sys.stdout)