Remove checkpatch, since it's tuned for C not C++ (#1250)

Co-authored-by: Eldred Habert <eldredhabert0@gmail.com>

.github/workflows/checkpatch.yml

@@ -1,25 +0,0 @@
-name: "Code style checking"
-on: pull_request
-
-jobs:
-  checkpatch:
-    runs-on: ubuntu-latest
-    steps:
-      - name: Set up repo
-        run: |
-          git clone -b "${{ github.event.pull_request.head.ref }}" "${{ github.event.pull_request.head.repo.clone_url }}" rgbds
-          cd rgbds
-          git remote add upstream "${{ github.event.pull_request.base.repo.clone_url }}"
-          git fetch upstream
-      - name: Set up checkpatch
-        working-directory: rgbds
-        run: |
-          wget 'https://raw.githubusercontent.com/torvalds/linux/master/scripts/checkpatch.pl'
-          chmod +x checkpatch.pl
-          wget 'https://raw.githubusercontent.com/torvalds/linux/master/scripts/const_structs.checkpatch'
-          wget 'https://raw.githubusercontent.com/torvalds/linux/master/scripts/spelling.txt'
-      - name: Checkpatch
-        working-directory: rgbds
-        run: |
-          make checkpatch CHECKPATCH=./checkpatch.pl "BASE_REF=${{ github.event.pull_request.base.sha }}" Q= | tee log
-          if grep -q ERROR: log; then exit 1; else exit 0; fi