Remove extraneous calls to GC.start()

lib/msf/core/exploit/ipv6.rb

@@ -76,7 +76,6 @@ module Exploit::Remote::Ipv6
 
     return if not @ipv6_icmp6_capture
     @ipv6_icmp6_capture = nil
-    GC.start()
   end
 
   #

modules/auxiliary/spoof/arp/arp_poisoning.rb

@@ -103,7 +103,6 @@ class Metasploit3 < Msf::Auxiliary
 
       if datastore['LISTENER']
         @listener.kill if @listener
-        GC.start()
       end
 
       if capture and @spoofing and not datastore['BROADCAST']