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.markup5ever-0.11.0.bazel b/third_party/rust/cargo/remote/BUILD.markup5ever-0.11.0.bazel
index b24ba93..84bd3b4 100644
--- a/third_party/rust/cargo/remote/BUILD.markup5ever-0.11.0.bazel
+++ b/third_party/rust/cargo/remote/BUILD.markup5ever-0.11.0.bazel
@@ -78,9 +78,9 @@
     # buildifier: leave-alone
     deps = [
         ":markup5ever_build_script",
-        "@raze__log__0_4_17//:log",
+        "@raze__log__0_4_20//:log",
         "@raze__phf__0_10_1//:phf",
-        "@raze__string_cache__0_8_4//:string_cache",
+        "@raze__string_cache__0_8_7//:string_cache",
         "@raze__tendril__0_4_3//:tendril",
     ],
 )