docs: update smoltcp version

Signed-off-by: Thibaut Vandervelden <thvdveld@vub.be>

README.md

@@ -144,7 +144,7 @@ To use the _smoltcp_ library in your project, add the following to `Cargo.toml`:
 
 ```toml
 [dependencies]
-smoltcp = "0.8.0"
+smoltcp = "0.10.0"
 ```
 
 The default configuration assumes a hosted environment, for ease of evaluation.
@@ -152,7 +152,7 @@ You probably want to disable default features and configure them one by one:
 
 ```toml
 [dependencies]
-smoltcp = { version = "0.8.0", default-features = false, features = ["log"] }
+smoltcp = { version = "0.10.0", default-features = false, features = ["log"] }
 ```
 
 ## Feature flags