py3: Fix syntax error in parameter unpacking

Don't use Python 2 syntax to unpack parameters in the function
defintion. Unpack manually parameters to be compatible with Python 3.

Change-Id: I2a8b82d0c860b0ca9bdeca7a35e6a2640a2c87e7

fuelclient/profiler.py

@@ -76,7 +76,8 @@ class Profiler(object):
         # write callgraph in dot format
         parser = gprof2dot.PstatsParser(self.profiler)
 
-        def get_function_name((filename, line, name)):
+        def get_function_name(args):
+            filename, line, name = args
             module = os.path.splitext(filename)[0]
             module_pieces = module.split(os.path.sep)
             return "{module:s}:{line:d}:{name:s}".format(