scripts: generate_rust_analyzer: Add pin_init_internal deps

Commit d7659acca7a3 ("rust: add pin-init crate build infrastructure")
did not add dependencies to `pin_init_internal`, resulting in broken
navigation. Thus add them now.

[ Tamir elaborates:

"before this series, go-to-symbol from pin_init_internal to e.g.
proc_macro::TokenStream doesn't work."

- Miguel ]

Signed-off-by: Tamir Duberstein <tamird@kernel.org>
Reviewed-by: Jesung Yang <y.j3ms.n@gmail.com>
Acked-by: Benno Lossin <lossin@kernel.org>
Fixes: d7659acca7a3 ("rust: add pin-init crate build infrastructure")
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20250723-rust-analyzer-pin-init-v1-3-3c6956173c78@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>