du: fix default symlink handling
du: fix default symlink handling

Fixes #776

uutils/coreutils,jbcrail/coreutils,wimh/coreutils,tempbottle/coreutils,dbrgn/coreutils,jbcrail/coreutils,kevgeniy/coreutils,kwantam/coreutils,keunwoo/coreutils,uutils/coreutils,kevgeniy/coreutils,ebfe/coreutils,Heather/coreutils,wimh/coreutils,kwantam/coreutils,Heather/coreutils,dbrgn/coreutils,tempbottle/coreutils,dbrgn/coreutils,Arcterus/coreutils,ebfe/coreutils,keunwoo/coreutils,Arcterus/coreutils,uutils/coreutils