FROMLIST: rust: don't select CONSTRUCTORS

This was originally part of commit 4b9a68f2e59a0 ("rust: add support for
static synchronisation primitives") from the old Rust branch, which used
module constructors to initialize globals containing various
synchronisation primitives with pin-init. That commit has never been
upstreamed, but the `select CONSTRUCTORS` statement ended up being
included in the patch that initially added Rust support to the Linux
Kernel.

We are not using module constructors, so let's remove the select.

Bug: 328029474
Link: https://lore.kernel.org/r/20240308-constructors-v1-1-4c811342391c@google.com


Change-Id: I8380b421a4e1a2b3b5334b47f3fafbc630376c05
Signed-off-by: Alice Ryhl <aliceryhl@google.com>