Add mvebu-cortexa9 trget

Author: sinegar

.github/workflows/build.yml

@@ -21,6 +21,7 @@ jobs:
         arch:
           - arm_arm1176jzf-s_vfp # RPi Zero
           - aarch64_cortex-a53   # RPi 3+
+          - mvebu-cortexa9
 
     steps:
       - uses: actions/checkout@v4