github: Move matrix-check.yml and patch-check.yml into lint.yml

It does not really make sense to maintain these in separate workflows
when they run in the exact same fashion.

Signed-off-by: Nathan Chancellor <nathan@kernel.org>

.github/workflows/lint.yml

@@ -1,9 +1,28 @@
-# Run a couple of linters on code in repo
-# * shellcheck and shfmt for shell scripts
-# * YAPF for Python scripts
+# Runs several checks
+# * check-matrix.sh because GitHub limits a workflow matrix to 256 jobs
+#   https://docs.github.com/en/actions/reference/usage-limits-billing-and-administration#usage-limits
+# * check-patches.sh to make sure applying patches via TuxSuite works correctly
+# * shellcheck for shell script correctness
+# * shfmt for shell script formatting consistency
+# * yapf for Python formatting consistency
+
 name: Lint checks
 on: [push, pull_request]
 jobs:
+  check_matrices:
+    name: Check workflow matrices
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: check-matrix.sh
+      run: bash check-matrix.sh
+  check_patch_series:
+    name: Check patches series
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: check-patches.sh
+      run: bash check-patches.sh
   shellcheck:
     uses: ClangBuiltLinux/actions-workflows/.github/workflows/shellcheck.yml@main
   shfmt: