Do not define bad_array_new_length::bad_array_new_length in libc++ anymore
when used in combinaison with libcxxrt since it is now defined there already.
This fixes building world


git-svn-id: svn+ssh://svn.freebsd.org/base/head@273434 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f