Convert data tuple to a list

The data parameter is defaulted to a tuple, to avoid a TypeError
this needs to be converted to a list before it can be concatenated
with another list.

Change-Id: Iba42196e9f9b9315b684a5ceadf16313f13fdd25

pyghmi/ipmi/private/session.py

@@ -717,7 +717,7 @@ class Session(object):
         if retry is None:
             retry = not self.servermode
         if self.servermode:
-            data = [code] + data
+            data = [code] + list(data)
             if netfn is None:
                 netfn = self.clientnetfn
             if command is None: