chore(ci): update check-doc Make task strategy for Rust components

This change updates a few strategies all of which reduce check time and
false positive failures:

- Remove `--all` flag which is deprecated for `--workspace` and is not
  the intended default behavior at a component/crate level (i.e. only
  check documentation for _this_ crate)
- Add `--all-features` to ensure that all feature-gated code
  documentation is also checked
- Add `--no-deps` flag which does not check documentation for
  dependencies

Signed-off-by: Fletcher Nichol <fletcher@systeminit.com>

mk/rust.mk

@@ -25,7 +25,7 @@ default--check-lint:
 ## check-doc: Checks all documentation for the Rust crate
 default--check-doc:
 	$(call header,$@)
-	env RUSTDOCFLAGS="-Dwarnings" cargo doc --all
+	env RUSTDOCFLAGS="-Dwarnings" cargo doc --all-features --no-deps
 .PHONY: default--check-doc
 
 ## check-format: Checks all code formatting for the Rust crate