run-tests: Rewrite detection of what tests we can try to execute

Autodetect whether we can run tests in Wine on unix.

.github/workflows/build.yml

@@ -86,7 +86,7 @@ jobs:
           LLVM_CMAKEFLAGS="-DLLVM_ENABLE_LIBXML2=OFF -DLLDB_ENABLE_PYTHON=OFF" ./build-all.sh $(pwd)/install/llvm-mingw
           .github/workflows/store-version.sh install/llvm-mingw/versions.txt
           ./test-libcxx-module.sh $(pwd)/install/llvm-mingw
-          RUN_I686=false RUN_X86_64=false ./run-tests.sh $(pwd)/install/llvm-mingw
+          ./run-tests.sh $(pwd)/install/llvm-mingw
           cd install
           DISTRO=ubuntu-$(grep DISTRIB_RELEASE /etc/lsb-release | cut -f 2 -d =)-$(uname -m)
           NAME=llvm-mingw-$TAG-ucrt-$DISTRO
@@ -131,7 +131,7 @@ jobs:
         run: |
           sudo apt-get update && sudo apt-get install qemu-user-static libc6-arm64-cross libstdc++6-arm64-cross
           QEMU_LD_PREFIX=/usr/aarch64-linux-gnu ./test-libcxx-module.sh $(pwd)/install/llvm-mingw
-          QEMU_LD_PREFIX=/usr/aarch64-linux-gnu RUN_I686=false RUN_X86_64=false ./run-tests.sh $(pwd)/install/llvm-mingw
+          QEMU_LD_PREFIX=/usr/aarch64-linux-gnu ./run-tests.sh $(pwd)/install/llvm-mingw
       - name: Package the toolchain
         env:
           TAG: ${{needs.prepare.outputs.TAG}}
@@ -175,7 +175,7 @@ jobs:
           # llvm-mingw).
           LLVM_CMAKEFLAGS="-DLLVM_ENABLE_LIBXML2=OFF" ./build-all.sh $(pwd)/install/llvm-mingw --disable-clang-tools-extra --disable-lldb --enable-asserts
           .github/workflows/store-version.sh install/llvm-mingw/versions.txt
-          RUN_I686=false RUN_X86_64=false ./run-tests.sh $(pwd)/install/llvm-mingw
+          ./run-tests.sh $(pwd)/install/llvm-mingw
           cd install
           tar -Jcf ../llvm-mingw-linux.tar.xz --format=ustar --numeric-owner --owner=0 --group=0 --sort=name --mtime="$BUILD_DATE" llvm-mingw
       - uses: actions/upload-artifact@v4
@@ -209,7 +209,7 @@ jobs:
           MACOS_REDIST=1 LLVM_CMAKEFLAGS="-DLLVM_ENABLE_ZSTD=OFF -DLLDB_ENABLE_PYTHON=OFF" ./build-all.sh $(pwd)/install/llvm-mingw
           .github/workflows/store-version.sh install/llvm-mingw/versions.txt
           ./test-libcxx-module.sh $(pwd)/install/llvm-mingw
-          RUN_I686=false RUN_X86_64=false ./run-tests.sh $(pwd)/install/llvm-mingw
+          ./run-tests.sh $(pwd)/install/llvm-mingw
           cd install
           NAME=llvm-mingw-$TAG-ucrt-macos-universal
           mv llvm-mingw $NAME