autopilot: remove support for 0.7.2 clighting

This is required becasue current `lightningd` will not start
when using a non-dynamic plugin.

Since clighting version 0.7.2 is very old, we can safely remove this
code.

autopilot/autopilot.py

@@ -11,6 +11,9 @@ import dns.resolver
 import time
 
 
+plugin = Plugin()
+
+
 class CLightning_autopilot(Autopilot):
 
     def __init__(self, rpc):
@@ -115,13 +118,6 @@ class CLightning_autopilot(Autopilot):
                 print("Could not open a channel to {} with capacity of {}. Error: {}".format(nodeid, satoshis, str(e)))
 
 
-try:
-    # C-lightning v0.7.2
-    plugin = Plugin(dynamic=False)
-except:
-    plugin = Plugin()
-
-
 @plugin.init()
 def init(configuration, options, plugin):
     plugin.num_channels = int(options['autopilot-num-channels'])