rust: init: broaden the blanket impl of Init

This makes it possible to use `T` as a `impl Init<T, E>` for every error
type `E` instead of just `Infallible`.

Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Link: https://lore.kernel.org/r/20230413100157.740697-1-benno.lossin@proton.me
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Author: BennoLossin

rust/kernel/init.rs

@@ -1190,8 +1190,8 @@ pub fn uninit<T, E>() -> impl Init<MaybeUninit<T>, E> {
 }
 
 // SAFETY: Every type can be initialized by-value.
-unsafe impl<T> Init<T> for T {
-    unsafe fn __init(self, slot: *mut T) -> Result<(), Infallible> {
+unsafe impl<T, E> Init<T, E> for T {
+    unsafe fn __init(self, slot: *mut T) -> Result<(), E> {
         unsafe { slot.write(self) };
         Ok(())
     }