rust: Alias rust_ffi_rlib to rust_library_rlib

With the new transition mutators, the distinctions between rust_ffi_rlib
and rust_library_rlib are not necessary. This CL removes the remaining
distinctions to allow an unusual use case where a rust_library and a
rust_ffi_rlib would otherwise be created from the same source. This
would allow defining a single rust_library_rlib that works for both rust
modules and cc modules.

One key change is that rust_ffi_rlibs only produced an rlib-std variant
previously, and now produce dylib-std variants as well.This surfaced an
issue where a libstd linkage mismatch would cause rustc to throw a
consufing missing crate error. We instead add logic to catch this in
Soong and provide a more useful error message.

Bug: 383552450
Test: m rust
Test: m blueprint_tests
Change-Id: I611ca46934059735d06229952cfd8e0ab7050486