Fix cross compilation on linux (#1050)

Author: rickardp

.github/workflows/python-package.yml

@@ -54,9 +54,9 @@ jobs:
         build_arch=${{ matrix.arch }}
         if [ ${build_os:0:6} == ubuntu -a ${build_arch} == aarch64 ]; then
           # Allow cross-compile om aarch64
-          sudo apt-get install -y gcc-aarch64-linux-gnu binutils-aarch64-linux-gnu
-        fi
-        if [ ${build_os:0:5} == macos -a ${build_arch} == aarch64 ]; then
+          sudo apt-get install -y gcc-aarch64-linux-gnu binutils-aarch64-linux-gnu g++-aarch64-linux-gnu
+          cmake -DCMAKE_C_COMPILER=aarch64-linux-gnu-gcc -DCMAKE_CXX_COMPILER=aarch64-linux-gnu-g++ -DCOMPUTE_BACKEND=cpu .
+        elif [ ${build_os:0:5} == macos -a ${build_arch} == aarch64 ]; then
           cmake -DCMAKE_OSX_ARCHITECTURES=arm64 -DCOMPUTE_BACKEND=cpu .
         else
           cmake -DCOMPUTE_BACKEND=cpu .