fix: Fix libunwind for old android (#6)

.github/workflows/build-cross-images.yml

@@ -68,7 +68,17 @@ jobs:
           repository: cross-rs/cross
           ref: ${{ env.CROSS_REPO_REF }}
           path: cross
-
+
+      - name: git patch (cross)
+        run: git apply ../patches/cross.patch
+        working-directory: ./cross
+
+      - name: Configure Android/NDK/SDK
+        working-directory: ./cross
+        run: |
+          grep 'ARG ANDROID_' ./docker/Dockerfile.*
+          grep 'libunwind.a' ./docker/android-system.sh || true
+          
       - uses: ./.github/actions/setup-rust
 
       - name: Set up Docker Buildx

patches/cross.patch

@@ -0,0 +1,16 @@
+diff --git a/docker/android-system.sh b/docker/android-system.sh
+index 412758f..2a97e9a 100755
+--- a/docker/android-system.sh
++++ b/docker/android-system.sh
+@@ -137,6 +137,11 @@ main() {
+     rm -rf "${td}"
+     rm -rf "${PYTHON_TMPDIR}"
+     rm "${0}"
++    # workaround
++    # https://blog.rust-lang.org/2023/01/09/android-ndk-update-r25.html
++    # https://github.com/rust-lang/rust/pull/85806#issuecomment-1096266946
++    find / -name 'libunwind.a' | sed '[email protected][email protected]@' | while read x; do echo "INPUT(-lunwind)" > $x; echo "Patched $x"; done
++    apt-get install --assume-yes --no-install-recommends libncurses5
+ }
+
+ # java isn't required for the build, but the build expects to