readme: list previous LTS releases (#5931)

Author: Darksonn

README.md

@@ -216,7 +216,6 @@ warrants a patch release with a fix for the bug, it will be backported and
 released as a new patch release for each LTS minor version. Our current LTS
 releases are:
 
- * `1.18.x` - LTS release until June 2023. (MSRV 1.49)
  * `1.20.x` - LTS release until September 2023. (MSRV 1.49)
  * `1.25.x` - LTS release until March 2024. (MSRV 1.49)
 
@@ -231,6 +230,12 @@ can use the following dependency specification:
 tokio = { version = "~1.18", features = [...] }
 ```
 
+### Previous LTS releases
+
+ * `1.8.x` - LTS release until February 2022.
+ * `1.14.x` - LTS release until June 2022.
+ * `1.18.x` - LTS release until June 2023.
+
 ## License
 
 This project is licensed under the [MIT license].

tokio/README.md

@@ -216,7 +216,6 @@ warrants a patch release with a fix for the bug, it will be backported and
 released as a new patch release for each LTS minor version. Our current LTS
 releases are:
 
- * `1.18.x` - LTS release until June 2023. (MSRV 1.49)
  * `1.20.x` - LTS release until September 2023. (MSRV 1.49)
  * `1.25.x` - LTS release until March 2024. (MSRV 1.49)
 
@@ -231,6 +230,12 @@ can use the following dependency specification:
 tokio = { version = "~1.18", features = [...] }
 ```
 
+### Previous LTS releases
+
+ * `1.8.x` - LTS release until February 2022.
+ * `1.14.x` - LTS release until June 2022.
+ * `1.18.x` - LTS release until June 2023.
+
 ## License
 
 This project is licensed under the [MIT license].