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.phf_shared-0.10.0.bazel b/third_party/rust/cargo/remote/BUILD.phf_shared-0.10.0.bazel
index fd8d2fa..d6f0480 100644
--- a/third_party/rust/cargo/remote/BUILD.phf_shared-0.10.0.bazel
+++ b/third_party/rust/cargo/remote/BUILD.phf_shared-0.10.0.bazel
@@ -52,6 +52,6 @@
     version = "0.10.0",
     # buildifier: leave-alone
     deps = [
-        "@raze__siphasher__0_3_10//:siphasher",
+        "@raze__siphasher__0_3_11//:siphasher",
     ],
 )