x11-wm/sway: unbreak X11=off build after r535134

../sway/commands/xwayland/scale.c:23:12: error: no member named 'xwayland' in 'struct sway_server'

if(server.xwayland.wlr_xwayland != NULL) {
   ~~~~~~ ^

../sway/commands/xwayland/scale.c:24:3: error: implicit declaration of function 'wlr_xwayland_set_scale' is invalid in C99 [-Werror,-Wimplicit-function-declaration]

wlr_xwayland_set_scale(server.xwayland.wlr_xwayland, scale);
^

../sway/commands/xwayland/scale.c:24:3: note: did you mean 'xwayland_cmd_scale'?
../sway/commands/xwayland/scale.c:7:21: note: 'xwayland_cmd_scale' declared here
struct cmd_results *xwayland_cmd_scale(int argc, char **argv) {

^

../sway/commands/xwayland/scale.c:24:33: error: no member named 'xwayland' in 'struct sway_server'

wlr_xwayland_set_scale(server.xwayland.wlr_xwayland, scale);
                       ~~~~~~ ^

PR: 246498
Reported by: shamaz.mazum@gmail.com