[OE-core] [PATCH] yocto-compat-layer.py: Fix trace when layers can't be processed

[Mark Hatle]

When all of the requested layers have unsatisfied dependencies, an error
can occur.  Check for the condition to avoid the traceback:

Traceback (most recent call last):
  File "../scripts/yocto-compat-layer.py", line 203, in <module>
    ret =  main()
  File "../scripts/yocto-compat-layer.py", line 194, in main
    if not results[layer_name].wasSuccessful():
AttributeError: 'NoneType' object has no attribute 'wasSuccessful'

Signed-off-by: Mark Hatle <mark.hatle at windriver.com>
---
 scripts/yocto-compat-layer.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/yocto-compat-layer.py b/scripts/yocto-compat-layer.py
index a16974f..9a541c6 100755
--- a/scripts/yocto-compat-layer.py
+++ b/scripts/yocto-compat-layer.py
@@ -191,7 +191,7 @@ def main():
         logger.info('')
         for layer_name in results_status:
             logger.info('%s ... %s' % (layer_name, results_status[layer_name]))
-            if not results[layer_name].wasSuccessful():
+            if not results[layer_name] or not results[layer_name].wasSuccessful():
                 ret = 2 # ret = 1 used for initialization errors
 
     cleanup_bblayers(None, None)
-- 
1.8.3.1