tidy-up: .gitignore lines mostly

- `.gitignore`: delete, dedupe and move rules upwards.
  Ref: 6389ba87b8 #13311
- `.gitignore`: fix generated test sources.
  Follow-up to 71cf0d1fca #14772
- `.gitignore`: replace exe listings with a wildcard.
- lib: move `setup-*.h` from `EXTRA_DIST` to `CURL_HFILES`.
- `makedebug.bat`: uppercase an argument to match docs.
- GHA/non-native: delete stray env.
  Follow-up to 12a6de2f66 #16043
- sort source lists.

Closes #16093

.github/workflows/non-native.yml

@@ -318,7 +318,6 @@ jobs:
       - name: 'configure'
         run: |
           if [ -n '${{ matrix.build.generate }}' ]; then
-            export OPENSSL_DIR=/
             # https://cmake.org/cmake/help/latest/manual/cmake-toolchains.7.html#cross-compiling-for-ios-tvos-visionos-or-watchos
             [ -n '${{ matrix.build.generator }}' ] && options='-G ${{ matrix.build.generator }}'
             cmake -B bld -DCMAKE_UNITY_BUILD=ON -DCURL_TEST_BUNDLES=ON -DCURL_WERROR=ON \