workspace: add Rust EFI infrastructure

This bumps rules_rust, cleans up the toolchains with the new version.
It also adds the Prost codegen to "normal" crate set as well as a new
crate set specific to EFI. This is separate because of Rust no-std's
dependence on create feature tags.

Change-Id: Ie76e66ee83696948391420ca3b011a3a71258690
Reviewed-on: https://review.monogon.dev/c/monogon/+/2202
Tested-by: Jenkins CI
Reviewed-by: Serge Bazanski <serge@monogon.tech>
diff --git a/third_party/rust/cargo/remote/BUILD.syn-2.0.37.bazel b/third_party/rust/cargo/remote/BUILD.syn-2.0.37.bazel
new file mode 100644
index 0000000..5cf9c62
--- /dev/null
+++ b/third_party/rust/cargo/remote/BUILD.syn-2.0.37.bazel
@@ -0,0 +1,125 @@
+"""
+@generated
+cargo-raze crate build file.
+
+DO NOT EDIT! Replaced on runs of cargo-raze
+"""
+
+# buildifier: disable=load
+load("@bazel_skylib//lib:selects.bzl", "selects")
+
+# buildifier: disable=load
+load(
+    "@rules_rust//rust:defs.bzl",
+    "rust_binary",
+    "rust_library",
+    "rust_proc_macro",
+    "rust_test",
+)
+
+package(default_visibility = [
+    # Public for visibility by "@raze__crate__version//" targets.
+    #
+    # Prefer access through "//third_party/rust/cargo", which limits external
+    # visibility to explicit Cargo.toml dependencies.
+    "//visibility:public",
+])
+
+licenses([
+    "notice",  # MIT from expression "MIT OR Apache-2.0"
+])
+
+# Generated Targets
+
+# Unsupported target "file" with type "bench" omitted
+
+# Unsupported target "rust" with type "bench" omitted
+
+rust_library(
+    name = "syn",
+    srcs = glob(["**/*.rs"]),
+    crate_features = [
+        "clone-impls",
+        "default",
+        "derive",
+        "full",
+        "parsing",
+        "printing",
+        "proc-macro",
+        "quote",
+        "visit",
+        "visit-mut",
+    ],
+    crate_root = "src/lib.rs",
+    data = [],
+    edition = "2021",
+    rustc_flags = [
+        "--cap-lints=allow",
+    ],
+    tags = [
+        "cargo-raze",
+        "crate-name=syn",
+        "manual",
+    ],
+    version = "2.0.37",
+    # buildifier: leave-alone
+    deps = [
+        "@raze__proc_macro2__1_0_67//:proc_macro2",
+        "@raze__quote__1_0_33//:quote",
+        "@raze__unicode_ident__1_0_12//:unicode_ident",
+    ],
+)
+
+# Unsupported target "regression" with type "test" omitted
+
+# Unsupported target "test_asyncness" with type "test" omitted
+
+# Unsupported target "test_attribute" with type "test" omitted
+
+# Unsupported target "test_derive_input" with type "test" omitted
+
+# Unsupported target "test_expr" with type "test" omitted
+
+# Unsupported target "test_generics" with type "test" omitted
+
+# Unsupported target "test_grouping" with type "test" omitted
+
+# Unsupported target "test_ident" with type "test" omitted
+
+# Unsupported target "test_item" with type "test" omitted
+
+# Unsupported target "test_iterators" with type "test" omitted
+
+# Unsupported target "test_lit" with type "test" omitted
+
+# Unsupported target "test_meta" with type "test" omitted
+
+# Unsupported target "test_parse_buffer" with type "test" omitted
+
+# Unsupported target "test_parse_stream" with type "test" omitted
+
+# Unsupported target "test_pat" with type "test" omitted
+
+# Unsupported target "test_path" with type "test" omitted
+
+# Unsupported target "test_precedence" with type "test" omitted
+
+# Unsupported target "test_receiver" with type "test" omitted
+
+# Unsupported target "test_round_trip" with type "test" omitted
+
+# Unsupported target "test_shebang" with type "test" omitted
+
+# Unsupported target "test_should_parse" with type "test" omitted
+
+# Unsupported target "test_size" with type "test" omitted
+
+# Unsupported target "test_stmt" with type "test" omitted
+
+# Unsupported target "test_token_trees" with type "test" omitted
+
+# Unsupported target "test_ty" with type "test" omitted
+
+# Unsupported target "test_visibility" with type "test" omitted
+
+# Unsupported target "zzz_stable" with type "test" omitted