PRECIOUS-Gold steady near 5-wk lows, heads for biggest weekly fall in 4

* Gold on track for second weekly fall * Silver set for biggest weekly fall in nearly 3 months * Platinum hovers near more than 4-month lows * U.S. Q1 Advance GDP due later in the day (Adds quotes, details; updates prices) By Swati Verma BENGALURU, April 27 (Reuters) - Gold prices languished near a five-week low on Friday, set for a decline of more than 1 percent this week, weighed down by a strong dollar, high U.S. Treasury yields and easing geo-political concerns.