rust: devres: initialize Devres::inner::data last

rust: devres: initialize Devres::inner::data last

Users may want to access the Devres object from callbacks registered
through the initialization of Devres::inner::data.

For those accesses to be valid, Devres::inner::data must be initialized
last [1].

Credit to Boqun for spotting this [2].

Link: https://lore.kernel.org/lkml/DBBPHO26CPBS.2OVI1OERCB2J5@kernel.org/
Link: https://lore.kernel.org/lkml/aHSmxWeIy3L-AKIV@Mac.home/
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250714113712.22158-1-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>