use qemu on github CI for ppc64le, s390x

Author: mattip

.github/workflows/posix.yml

@@ -46,6 +46,12 @@ jobs:
           - { os: ubuntu-24.04-arm, PLAT: aarch64, INTERFACE64: '0', MB_ML_VER: '_1_2', MB_ML_LIBC: musllinux}
           - { os: ubuntu-24.04-arm, PLAT: aarch64, INTERFACE64: '1', MB_ML_VER: '_1_2', MB_ML_LIBC: musllinux}
 
+          - { os: ubuntu-latest, PLAT: ppc64le, INTERFACE64: '0', MB_ML_VER: '2014', MB_ML_LIBC: manylinux}
+          - { os: ubuntu-latest, PLAT: ppc64le, INTERFACE64: '1', MB_ML_VER: '2014', MB_ML_LIBC: manylinux}
+
+          - { os: ubuntu-latest, PLAT: s390x, INTERFACE64: '0', MB_ML_VER: '2014', MB_ML_LIBC: manylinux}
+          - { os: ubuntu-latest, PLAT: s390x, INTERFACE64: '1', MB_ML_VER: '2014', MB_ML_LIBC: manylinux}
+
     env:
       NIGHTLY: ${{ github.event_name == 'schedule' || github.event_name == 'workflow_dispatch' }}
       MB_ML_LIBC: ${{ matrix.MB_ML_LIBC }}
@@ -71,6 +77,12 @@ jobs:
       with:
         xcode-version: '15.4'
 
+    - name: Set up QEMU
+      if: runner.os == 'Linux' && runner.arch == 'X64'
+      uses: docker/setup-qemu-action@v3
+      with:
+        platforms: all
+
     - name: Print some Environment variable
       run: |
         echo "PLAT: ${PLAT}"

tools/build_steps.sh

@@ -163,11 +163,14 @@ function do_build_lib {
             export SDKROOT=${SDKROOT:-$(xcrun --show-sdk-path)}
             ;;
         *-s390x)
+            # The TargetList.txt has only ZARCH_GENERIC, Z13, Z14. Not worth
+            # messing with dynamic lists and targets.
             local bitness=64
             ;;
         *-ppc64le)
             local bitness=64
             local target="POWER8"
+            local dynamic_list="POWER8 POWER10"
             ;;
         Linux-loongarch64)
             local target="GENERIC"