Silent a Rust compiler warning on invalid reference casting

Using such a cast to set the `dr` register inside an `unsafe` block is
an acceptable way to access the data.

Author: samueltardieu

CHANGELOG.md

@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 - Move from bors/manual merge to GH merge queue
 - Add tools/check.py python script for local check
 - Add changelog check on PRs
+- Fix a compiler warning when casting a reference
 
 ## [v0.10.0] - 2022-12-12
 

src/spi.rs

@@ -353,6 +353,7 @@ where
         unsafe { ptr::read_volatile(&self.spi.dr as *const _ as *const FrameSize) }
     }
 
+    #[allow(invalid_reference_casting)]
     fn write_data_reg(&mut self, data: FrameSize) {
         // NOTE(write_volatile) see note above
         unsafe { ptr::write_volatile(&self.spi.dr as *const _ as *mut FrameSize, data) }