Fix according to latest clippy (#17)

* Install rustfmt & clippy explicitly in CI

* Adjust clippy setting from cli

Author: xxuejie

.github/workflows/rust.yml

@@ -18,6 +18,8 @@ jobs:
     - name: Install llvm
       run: sudo apt update && sudo apt install -y clang llvm clang-format lld
     - uses: actions-rust-lang/setup-rust-toolchain@v1
+      with:
+        components: rustfmt, clippy
     - name: Prepare, build, test, clippy, format
       run: make prepare build test clippy fmt
     - name: git diff
@@ -45,5 +47,7 @@ jobs:
     - name: Install latest llvm & lld
       run: brew install llvm lld
     - uses: actions-rust-lang/setup-rust-toolchain@v1
+      with:
+        components: rustfmt, clippy
     - name: Prepare, build, test, clippy
       run: make prepare build test clippy

Makefile

@@ -83,7 +83,7 @@ check:
 	cargo check $(CARGO_ARGS)
 
 clippy:
-	cargo clippy $(CARGO_ARGS)
+	cargo clippy $(CARGO_ARGS) -- -A clippy::manual-is-multiple-of
 
 fmt:
 	cargo fmt $(CARGO_ARGS)