compositor-wayland: Convert sprawl flag to boolean

Signed-off-by: Armin Krezović <krezovic.armin@gmail.com>
Reviewed-by: Quentin Glidic <sardemff7+git@sardemff7.net>
diff --git a/libweston/compositor-wayland.c b/libweston/compositor-wayland.c
index d1ff8d7..32c44d4 100644
--- a/libweston/compositor-wayland.c
+++ b/libweston/compositor-wayland.c
@@ -76,7 +76,7 @@
 	} parent;
 
 	bool use_pixman;
-	int sprawl_across_outputs;
+	bool sprawl_across_outputs;
 	int fullscreen;
 
 	struct theme *theme;
@@ -2448,7 +2448,7 @@
 		return -1;
 
 	if (new_config.sprawl || b->parent.fshell) {
-		b->sprawl_across_outputs = 1;
+		b->sprawl_across_outputs = true;
 		wl_display_roundtrip(b->parent.wl_display);
 
 		wl_list_for_each(poutput, &b->parent.output_list, link)