drm/i915: kill warning in intel_find_pll_g4x_dp

Initialize clock.vco to silence gcc.

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 7eed3db..3ba6546b 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -943,6 +943,7 @@
     clock.m = 5 * (clock.m1 + 2) + (clock.m2 + 2);
     clock.p = (clock.p1 * clock.p2);
     clock.dot = 96000 * clock.m / (clock.n + 2) / clock.p;
+    clock.vco = 0;
     memcpy(best_clock, &clock, sizeof(intel_clock_t));
     return true;
 }