Fix None value

git-svn-id: https://redmine.imt-atlantique.fr/svn/xaal/code/Python/trunk@2055 b32b6428-25c9-4566-ad07-03861ab6144f

devices/loggers/warp10/xaal/warp10/dev.py

@@ -49,6 +49,7 @@ class WARP10Logger:
                 name = '%s.%s' % (base,k)
                 tags  = '{devid=%s}' % msg.source
                 value = msg.body[k]
+                if value != None:
                     buf = buf +"%s// %s%s %s\n" % (now,name,tags,value)
             DATA_BUF = DATA_BUF + buf
             self.push()