[build-script] When cross compiling tools, don't install native host tools.

Author: Doug Coleman

utils/build-script-impl

@@ -2781,6 +2781,11 @@ for host in "${ALL_HOSTS[@]}"; do
         continue
     fi
 
+    # Skip this if we're cross compiling and it's the local host.
+    if [[ $(has_cross_compile_hosts) ]] && [[ ${host} == ${LOCAL_HOST} ]]; then
+        continue
+    fi
+
     # Calculate the directory to install products in to.
     host_install_destdir=$(get_host_install_destdir ${host})
     host_install_prefix=$(get_host_install_prefix ${host})