simplify WMWritePropListToFile()

remove the choice of atomic/non-atomic writes. firstly, the only users
of non-atomic writes were getstyle and geticonset; secondly, who in their
right minds would ever want non-atomic writes; thirdly, the file system
will screw you anyway *G*.

util/setstyle.c

@@ -536,7 +536,7 @@ int main(int argc, char **argv)
 
 	WMMergePLDictionaries(prop, style, True);
 
-	WMWritePropListToFile(prop, path, True);
+	WMWritePropListToFile(prop, path);
 	{
 		XEvent ev;