Linux build: try to support cross-builds

Author: lool

scripts/build-linux-deb.sh

@@ -72,11 +72,11 @@ touch kernel/configs/local.config
 for c in ${EXTRA_CONFIGS}; do
     echo "${c}" >>kernel/configs/local.config
 done
-make "${CONFIG}" local.config
+ARCH=arm64 make "${CONFIG}" local.config
 
 log_i "Building Linux deb"
 # TODO: build other packages?
-make -j$(nproc) bindeb-pkg
+ARCH=arm64 make -j$(nproc) bindeb-pkg
 
 ls
 ls ..