patch 8.0.1136: W_WIDTH() is always the same

Problem:    W_WIDTH() is always the same.
Solution:   Expand the macro.
diff --git a/src/quickfix.c b/src/quickfix.c
index 4625db9..850fa7b 100644
--- a/src/quickfix.c
+++ b/src/quickfix.c
@@ -3148,7 +3148,7 @@
 	{
 	    if (cmdmod.split & WSP_VERT)
 	    {
-		if (height != W_WIDTH(win))
+		if (height != win->w_width)
 		    win_setwidth(height);
 	    }
 	    else if (height != win->w_height)