module: don't expose "name" parameter for ArgValidator.validate()

The "name" argument is an implementation detail, that is used
by ArgValidatorDict and ArgValidatorList to pass a complex (nested)
name of what is currently parsed.

Callers are not supposed to see or use this argument.
Hide it, by adding an internal helper method _validate().

module_utils/network_lsr/argument_validator.py

@@ -91,14 +91,16 @@ class ArgValidator:
         except Exception:  # pylint: disable=broad-except
             return self.default_value
 
-    def _validate_impl(self, value, name):
-        raise NotImplementedError()
+    def validate(self, value):
+        return self._validate(value, self.name)
 
-    def validate(self, value, name=None):
-        name = name or self.name or ""
+    def _validate(self, value, name):
         validated = self._validate_impl(value, name)
         return self._validate_post(value, name, validated)
 
+    def _validate_impl(self, value, name):
+        raise NotImplementedError()
+
     # pylint: disable=unused-argument,no-self-use
     def _validate_post(self, value, name, result):
         return result
@@ -227,7 +229,7 @@ class ArgValidatorDict(ArgValidator):
             if validator is None:
                 raise ValidationError(name, "invalid key '%s'" % (k))
             try:
-                vv = validator.validate(v, name + "." + k)
+                vv = validator._validate(v, name + "." + k)
             except ValidationError as e:
                 raise ValidationError(e.name, e.error_message)
             result[k] = vv
@@ -258,7 +260,7 @@ class ArgValidatorList(ArgValidator):
         result = []
         for (idx, v) in enumerate(value):
             try:
-                vv = self.nested.validate(v, name + "[" + str(idx) + "]")
+                vv = self.nested._validate(v, name + "[" + str(idx) + "]")
             except ValidationError as e:
                 raise ValidationError(e.name, e.error_message)
             result.append(vv)