ci: split out MSRV clippy job

Previously there was one job that ran clippy across all supported
operating systems for both the latest stable, and the MSRV Rust
toolchains.

This commit splits that job into two: one for stable and one for the
MSRV toolchain. This will make it easier to customize MSRV specific
settings in a subsequent commit.

Author: cpu

.github/workflows/ci.yml

@@ -22,18 +22,13 @@ jobs:
           - ubuntu-latest
           - macos-latest
           - windows-latest
-        rust:
-          - stable
-          # MSRV
-          - 1.56.0
     steps:
       - uses: actions/checkout@v3
         with:
           persist-credentials: false
 
-      - uses: dtolnay/rust-toolchain@master
+      - uses: dtolnay/rust-toolchain@stable
         with:
-          toolchain: ${{ matrix.rust }}
           components: clippy
 
       - name: Clippy (${{ matrix.os }})
@@ -59,6 +54,46 @@ jobs:
       #     rustup target add wasm32-unknown-unknown
       #     cargo clippy-ci --target wasm32-unknown-unknown
 
+  clippy-msrv:
+    name: Clippy (MSRV)
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os:
+          - ubuntu-latest
+          - macos-latest
+          - windows-latest
+    steps:
+      - uses: actions/checkout@v3
+        with:
+          persist-credentials: false
+
+      - uses: dtolnay/rust-toolchain@master
+        with:
+          toolchain: "1.56.0" # MSRV
+          components: clippy
+
+      - name: Install cargo-ndk.
+        run: |
+          cargo install cargo-ndk
+          rustup target add aarch64-linux-android
+
+      - name: Clippy (${{ matrix.os }})
+        run: cargo clippy-ci
+
+      - name: Clippy (Android)
+        if: matrix.os == 'ubuntu-latest'
+        run: |
+          cargo ndk -t arm64-v8a clippy-ci 
+
+      - name: Clippy (iOS)
+        if: matrix.os == 'macos-latest'
+        run: |
+          rustup target add x86_64-apple-ios
+          cargo clippy-ci  --target x86_64-apple-ios
+
+      # TODO: Consider WASM. See note on "clippy" job.
+
   test:
     name: Test
     runs-on: ${{ matrix.os }}