[github-actions] Windows: add matrix to build for x86_64 and i686
diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index b83f408..cde2dc7 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -43,15 +43,23 @@
     defaults:
       run:
         shell: msys2 {0}
+    strategy:
+      fail-fast: false
+      matrix:
+        include: [
+          { msystem: MINGW64, arch: x86_64 },
+          { msystem: MINGW32, arch: i686   }
+        ]
     steps:
     - uses: msys2/setup-msys2@v2
       with:
+        msystem: ${{ matrix.msystem }}
         release: false
         update: false
         install: >-
           base-devel
           git
-          mingw-w64-x86_64-gcc
+          mingw-w64-${{ matrix.arch }}-gcc
           make
           libtool
           autoconf