hack/util: take other arches into account on Darwin

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

hack/util

@@ -22,9 +22,12 @@ else
 fi
 
 if [ -z "$CLI_PLATFORM" ]; then
-  rawos=$(uname -s)
-  if [ "$rawos" = "Darwin" ]; then
-    CLI_PLATFORM="darwin/amd64"
+  if [ "$(uname -s)" = "Darwin" ]; then
+      arch="$(uname -m)"
+      if [ "$arch" = "x86_64" ]; then
+          arch="amd64"
+      fi
+      CLI_PLATFORM="darwin/$arch"
   elif uname -s | grep MINGW > /dev/null 2>&1 ; then
     CLI_PLATFORM="windows/amd64"
   fi