Dx12 HAL texture: expose raw resource (#6502)

Co-authored-by: Adam Winiarczuk <tsu@liv.tv>

wgpu-hal/src/dx12/mod.rs

@@ -777,6 +777,12 @@ pub struct Texture {
     allocation: Option<suballocation::AllocationWrapper>,
 }
 
+impl Texture {
+    pub unsafe fn raw_resource(&self) -> &Direct3D12::ID3D12Resource {
+        &self.resource
+    }
+}
+
 impl crate::DynTexture for Texture {}
 impl crate::DynSurfaceTexture for Texture {}