cc/rust: Alias ffi rlib variant for static_libs

Alias the rlib variant to "link: static". This allows declaring
rust_ffi_rlib modules in static_libs. This effectively removes any
distinction between rust_ffi_static and rust_ffi_rlib. Removing the
functionality for building Rust staticlib modules will be cleaned up in
a follow-on CL.

This should have the effect of changing the default linkage for all rust
modules in static_libs from linking individual staticlibs to building a
single staticlib that includes all rust_ffi rlib dependencies.

This removes the static_rlibs property, as we're now handling
the choice dynamically. This also makes rlibs only propagate through
cc_library_static modules if the rlib is included in
whole_static_lib. This both mirrors the expected behavior of
cc libraries and helps control which version of a crate ends up in the
final link (e.g. libdoh_ffi vs libdoh_ffi_for_test).

Bug: 254469782
Test: m
Test: m blueprint_tests
Change-Id: I2925f67f6dc9329dae3dcccafb8560900ac8a6fc

rust/fuzz_test.go

@@ -114,17 +114,23 @@ func TestCCFuzzDepBundling(t *testing.T) {
 				srcs: ["foo.rs"],
 				shared_libs: ["libcc_transitive_dep"],
 			}
+			rust_ffi_static {
+				name: "libtest_fuzzing_static",
+				crate_name: "test_fuzzing",
+				srcs: ["foo.rs"],
+				shared_libs: ["libcc_transitive_dep"],
+			}
 			cc_fuzz {
 				name: "fuzz_shared_libtest",
 				shared_libs: ["libtest_fuzzing"],
 			}
 			cc_fuzz {
 				name: "fuzz_static_libtest",
-				static_rlibs: ["libtest_fuzzing"],
+				static_libs: ["libtest_fuzzing"],
 			}
 			cc_fuzz {
 				name: "fuzz_staticffi_libtest",
-				static_libs: ["libtest_fuzzing"],
+				static_libs: ["libtest_fuzzing_static"],
 			}
 	`)