`GspInitDone` has no payload whatsoever, so the unit type `()` is the
correct way to represent its message content. We can use it now that
`()` implements `FromBytes`.

Reviewed-by: Alistair Popple <apopple@nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
---
 drivers/gpu/nova-core/gsp/commands.rs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/nova-core/gsp/commands.rs b/drivers/gpu/nova-core/gsp/commands.rs
index 0425c65b5d6f..2050771f9b53 100644
--- a/drivers/gpu/nova-core/gsp/commands.rs
+++ b/drivers/gpu/nova-core/gsp/commands.rs
@@ -142,7 +142,7 @@ fn init_variable_payload(
 }
 
 /// Message type for GSP initialization done notification.
-struct GspInitDone {}
+struct GspInitDone;
 
 // SAFETY: `GspInitDone` is a zero-sized type with no bytes, therefore it
 // trivially has no uninitialized bytes.
@@ -151,13 +151,13 @@ unsafe impl FromBytes for GspInitDone {}
 impl MessageFromGsp for GspInitDone {
     const FUNCTION: MsgFunction = MsgFunction::GspInitDone;
     type InitError = Infallible;
-    type Message = GspInitDone;
+    type Message = ();
 
     fn read(
         _msg: &Self::Message,
         _sbuffer: &mut SBufferIter<array::IntoIter<&[u8], 2>>,
     ) -> Result<Self, Self::InitError> {
-        Ok(GspInitDone {})
+        Ok(GspInitDone)
     }
 }
 

-- 
2.52.0