Mark DmaDescriptors as Send (#2456)

Co-authored-by: Dominic Fischer <git@dominicfischer.me>

esp-hal/CHANGELOG.md

@@ -23,6 +23,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - `UartInterrupt` and related functions (#2406)
 - I2S Parallel output driver for ESP32. (#2348, #2436)
 - Add an option to configure `WDT` action (#2330)
+- `DmaDescriptor` is now `Send` (#2456)
 
 ### Changed
 

esp-hal/src/dma/mod.rs

@@ -351,6 +351,11 @@ impl DmaDescriptor {
     }
 }
 
+// The pointers in the descriptor can be Sent.
+// Marking this Send also allows DmaBuffer implementations to automatically be
+// Send (where the compiler sees fit).
+unsafe impl Send for DmaDescriptor {}
+
 use enumset::{EnumSet, EnumSetType};
 
 pub use self::buffers::*;