Fix color with FAINT attribute

The alpha value needs to be initialized as well.

x.c

@@ -1193,6 +1193,7 @@ xdrawglyphfontspecs(const XftGlyphFontSpec *specs, Glyph base, int len, int x, i
 		colfg.red = fg->color.red / 2;
 		colfg.green = fg->color.green / 2;
 		colfg.blue = fg->color.blue / 2;
+		colfg.alpha = fg->color.alpha;
 		XftColorAllocValue(xw.dpy, xw.vis, xw.cmap, &colfg, &revfg);
 		fg = &revfg;
 	}