Fix diff_ignore_lines option issue in {eos,ios,nxos}_config module

* diff_ignore_lines option is to handle the running config fetch from
  remote host and ignore the lines that are auto updated eg: commit time and date
* This option should not be used while processing candidate (input) configuration

lib/ansible/modules/network/eos/eos_config.py

@@ -273,7 +273,7 @@ from ansible.module_utils.network.eos.eos import check_args
 
 
 def get_candidate(module):
-    candidate = NetworkConfig(indent=3, ignore_lines=module.params['diff_ignore_lines'])
+    candidate = NetworkConfig(indent=3)
     if module.params['src']:
         candidate.load(module.params['src'])
     elif module.params['lines']:

lib/ansible/modules/network/ios/ios_config.py

@@ -364,7 +364,7 @@ def get_running_config(module, current_config=None, flags=None):
 
 
 def get_candidate(module):
-    candidate = NetworkConfig(indent=1, ignore_lines=module.params['diff_ignore_lines'])
+    candidate = NetworkConfig(indent=1)
     banners = {}
 
     if module.params['src']:

lib/ansible/modules/network/nxos/nxos_config.py

@@ -300,7 +300,7 @@ def get_running_config(module, config=None):
 
 
 def get_candidate(module):
-    candidate = NetworkConfig(indent=2, ignore_lines=module.params['diff_ignore_lines'])
+    candidate = NetworkConfig(indent=2)
     if module.params['src']:
         if module.params['replace'] != 'config':
             candidate.load(module.params['src'])