Revert hte xattr dep change

(Portage version: 2.2.11/cvs/Linux x86_64, signed Manifest commit with key 0x65E309F2189DB0B8)
added prefix support (bug #433736)
added prefix support (bug #518898)

(Portage version: 2.2.8-r1/cvs/Linux x86_64, signed Manifest commit with key C2000586)
added prefix support (bug #518970)

(Portage version: 2.2.8-r1/cvs/Linux x86_64, signed Manifest commit with key C2000586)
Stable for HPPA (bug #517894).

(Portage version: 2.2.11/cvs/Linux x86_64, RepoMan options: --ignore-arches, signed Manifest commit with key A792A613)
sparc stable wrt #480692

(Portage version: 2.2.8-r1/cvs/Linux x86_64, signed Manifest commit with key 0xF6AD3240)