weston: Make the shell entrypoint specific

This avoids loading a shell as a module, so we are sure to have only one
shell loaded at a time.

Signed-off-by: Quentin Glidic <sardemff7+git@sardemff7.net>
Reviewed-by: Daniel Stone <daniels@collabora.com>
diff --git a/desktop-shell/shell.c b/desktop-shell/shell.c
index 5e10924..d8ef3fd 100644
--- a/desktop-shell/shell.c
+++ b/desktop-shell/shell.c
@@ -4874,8 +4874,8 @@
 }
 
 WL_EXPORT int
-wet_module_init(struct weston_compositor *ec,
-		int *argc, char *argv[])
+wet_shell_init(struct weston_compositor *ec,
+	       int *argc, char *argv[])
 {
 	struct weston_seat *seat;
 	struct desktop_shell *shell;