Nikkei drifts lower ahead of Greek vote, Fast Retailing slides

* Nikkei slips 0.4 pct, Topix dips 0.1 pct * Fast Retailing slides after June drop in Uniqlo sales * Cross-shareholding reduction plan lifts SMFG By Shinichi Saoshiro TOKYO, July 3 (Reuters) - Japan's Nikkei share average drifted lower on Friday as caution ahead of a Greek national vote over the weekend suppressed investors' appetite for risk, with Fast Retailing Co sliding after it reported a drop in domestic sales. The Nikkei share average lost 0.4 percent to 20,431.25 by