(copy_internal): Move the block that sets `earlier_file'

(copy_internal): Move the block that sets `earlier_file'
down to just before the first use of that variable.  Otherwise, it was
possible to make mv (and probably cp, too) malfunction when copying
hard-linked files into a directory containing at least one of the
source file names.  Call forget_created everywhere thereafter where
this function returns without creating a destination file that might
subsequently be linked.  Reported by Iida Yosiaki.