Add registry md file for disk attributes (#555)

Signed-off-by: ChrsMark <chrismarkou92@gmail.com>

docs/attributes-registry/README.md

@@ -34,6 +34,7 @@ Currently, the following namespaces exist:
 * [DB](db.md) (database)
 * [Destination](destination.md)
 * [Device](device.md)
+* [Disk](disk.md)
 * [Error](error.md)
 * [Host](host.md)
 * [HTTP](http.md)

docs/attributes-registry/disk.md

@@ -0,0 +1,19 @@
+<!--- Hugo front matter used to generate the website version of this page:
+--->
+
+# Disk
+
+## Disk Attributes
+
+<!-- semconv registry.disk(omit_requirement_level) -->
+| Attribute  | Type | Description  | Examples  |
+|---|---|---|---|
+| `disk.io.direction` | string | The disk IO operation direction. | `read` |
+
+`disk.io.direction` MUST be one of the following:
+
+| Value  | Description |
+|---|---|
+| `read` | read |
+| `write` | write |
+<!-- endsemconv -->

docs/system/system-metrics.md

@@ -359,7 +359,7 @@ This metric is [recommended][MetricRecommended].
 <!-- semconv metric.system.disk.io(full) -->
 | Attribute  | Type | Description  | Examples  | Requirement Level |
 |---|---|---|---|---|
-| `disk.io.direction` | string | The disk IO operation direction. | `read` | Recommended |
+| [`disk.io.direction`](../attributes-registry/disk.md) | string | The disk IO operation direction. | `read` | Recommended |
 | `system.device` | string | The device identifier | `(identifier)` | Recommended |
 
 `disk.io.direction` MUST be one of the following:
@@ -383,7 +383,7 @@ This metric is [recommended][MetricRecommended].
 <!-- semconv metric.system.disk.operations(full) -->
 | Attribute  | Type | Description  | Examples  | Requirement Level |
 |---|---|---|---|---|
-| `disk.io.direction` | string | The disk IO operation direction. | `read` | Recommended |
+| [`disk.io.direction`](../attributes-registry/disk.md) | string | The disk IO operation direction. | `read` | Recommended |
 | `system.device` | string | The device identifier | `(identifier)` | Recommended |
 
 `disk.io.direction` MUST be one of the following:
@@ -435,7 +435,7 @@ This metric is [recommended][MetricRecommended].
 <!-- semconv metric.system.disk.operation_time(full) -->
 | Attribute  | Type | Description  | Examples  | Requirement Level |
 |---|---|---|---|---|
-| `disk.io.direction` | string | The disk IO operation direction. | `read` | Recommended |
+| [`disk.io.direction`](../attributes-registry/disk.md) | string | The disk IO operation direction. | `read` | Recommended |
 | `system.device` | string | The device identifier | `(identifier)` | Recommended |
 
 `disk.io.direction` MUST be one of the following:
@@ -459,7 +459,7 @@ This metric is [recommended][MetricRecommended].
 <!-- semconv metric.system.disk.merged(full) -->
 | Attribute  | Type | Description  | Examples  | Requirement Level |
 |---|---|---|---|---|
-| `disk.io.direction` | string | The disk IO operation direction. | `read` | Recommended |
+| [`disk.io.direction`](../attributes-registry/disk.md) | string | The disk IO operation direction. | `read` | Recommended |
 | `system.device` | string | The device identifier | `(identifier)` | Recommended |
 
 `disk.io.direction` MUST be one of the following: