libweston: make weston_output::connection_internal a bool

It really is a boolean.

Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>
Reviewed-by: Armin Krezović <krezovic.armin@gmail.com>
diff --git a/libweston/compositor-drm.c b/libweston/compositor-drm.c
index 10adb46..c51d24b 100644
--- a/libweston/compositor-drm.c
+++ b/libweston/compositor-drm.c
@@ -2653,7 +2653,7 @@
 	find_and_parse_output_edid(b, output, output->connector);
 	if (output->connector->connector_type == DRM_MODE_CONNECTOR_LVDS ||
 	    output->connector->connector_type == DRM_MODE_CONNECTOR_eDP)
-		output->base.connection_internal = 1;
+		output->base.connection_internal = true;
 
 	weston_plane_init(&output->cursor_plane, b->compositor,
 			  INT32_MIN, INT32_MIN);