Fixes pylint errors (#23279)

Reported by gundalow, this fixes pylint errors in F5 modules

lib/ansible/modules/network/f5/bigip_gtm_datacenter.py

@@ -320,7 +320,7 @@ class BigIpGtmDatacenter(object):
         enabled = self.params['enabled']
 
         if state is None and enabled is None:
-            module.fail_json(msg="Neither 'state' nor 'enabled' set")
+            raise F5ModuleError("Neither 'state' nor 'enabled' set")
 
         try:
             if state == "present":

lib/ansible/modules/network/f5/bigip_routedomain.py

@@ -476,18 +476,12 @@ class BigIpRouteDomain(object):
         result = dict()
         state = self.params['state']
 
-        if self.params['check_mode']:
-            if value == current:
-                changed = False
-            else:
-                changed = True
-        else:
-            if state == "present":
-                changed = self.present()
-                current = self.read()
-                result.update(current)
-            elif state == "absent":
-                changed = self.absent()
+        if state == "present":
+            changed = self.present()
+            current = self.read()
+            result.update(current)
+        elif state == "absent":
+            changed = self.absent()
 
         result.update(dict(changed=changed))
         return result

lib/ansible/modules/network/f5/bigip_ssl_certificate.py

@@ -444,6 +444,8 @@ class BigIpSslCertificate(object):
 
     def delete(self):
         changed = False
+        name = self.params['name']
+        partition = self.params['partition']
 
         check_mode = self.params['check_mode']