Jenkins: Force macx-clang_bin-pkg config to Mac mini nodes

Bin pkg stage seems to require more disk space and it tends to
run out on virtual node.

Change-Id: Ie0d59914418c44c255f526933d4295c34b8bd72e
Reviewed-by: Tony Sarajärvi <tony.sarajarvi@digia.com>
Reviewed-by: Heikki Halmet <heikki.halmet@digia.com>