Remove BB_SH define entirely.
diff --git a/chroot.c b/chroot.c
index 0440e46..de6a2ea 100644
--- a/chroot.c
+++ b/chroot.c
@@ -48,7 +48,7 @@
 		prog = *argv;
 		execvp(*argv, argv);
 	} else {
-#if defined(BB_SH) && defined BB_FEATURE_SH_STANDALONE_SHELL
+#if defined shell_main && defined BB_FEATURE_SH_STANDALONE_SHELL
 		char shell[] = "/bin/sh";
 		char *shell_argv[2] = { shell, NULL };
 		applet_name = shell;