system-config: some options should not be under <log> section

Signed-off-by: Daijiro Fukuda <fukuda@clear-code.com>

Author: daipom

deployment/system-config.md

@@ -186,6 +186,23 @@ Force disable the shared socket which is for listening a same port across multip
 
 Enable JIT for worker processes. Internally, this configuration enables Ruby's `--jit` command-line option.
 
+### `enable_input_metrics`
+
+| type | default | version |
+| :--- | :---    | :---    |
+| bool | nil     | 1.14.0  |
+
+Specifies whether measuring input metrics should be enabled or not.
+
+### `enable_size_metrics`
+
+| type | default | version |
+| :--- | :---    | :---    |
+| bool | nil     | 1.14.0  |
+
+Specifies whether measuring record size metrics should be enabled or not.
+It can be useful for calculating flow rate on Fluentd instances.
+
 ### `<log>` section
 
 #### `path`
@@ -242,23 +259,6 @@ NOTE: When enabling log rotation on Windows, log files are separated into `log-s
 
 Please see also [Log Rotation Setting](logging.md#log-rotation-setting).
 
-#### `enable_input_metrics`
-
-| type | default | version |
-| :--- | :---    | :---    |
-| bool | nil     | 1.14.0  |
-
-Specifies whether measuring input metrics should be enabled or not.
-
-#### `enable_size_metrics`
-
-| type | default | version |
-| :--- | :---    | :---    |
-| bool | nil     | 1.14.0  |
-
-Specifies whether measuring record size metrics should be enabled or not.
-It can be useful for calculating flow rate on Fluentd instances.
-
 ### `<source_only_buffer>` section
 
 The temporary buffer setting for [Source Only Mode](source-only-mode.md).