Merge pull request #706 from ColinFinck/patch-1

Update embedded-io README for defmt feature and MSRV

Author: eldruin

embedded-io/README.md

@@ -23,11 +23,11 @@ targets.
 
 - **`std`**: Adds `From` impls to convert to/from `std::io` structs.
 - **`alloc`**: Adds blanket impls for `Box`, adds `Write` impl to `Vec`.
-- **`defmt-03`**: Derive `defmt::Format` from `defmt` 0.3 for enums and structs.
+- **`defmt`**: Derive `defmt::Format` from `defmt` 1.x for enums and structs.
 
 ## Minimum Supported Rust Version (MSRV)
 
-This crate is guaranteed to compile on stable Rust 1.60 and up. It *might*
+This crate is guaranteed to compile on stable Rust 1.81 and up. It *might*
 compile with older versions but that may change in any new patch release.
 
 See [here](../docs/msrv.md) for details on how the MSRV may be upgraded.