Deal with missing exports for hostfs

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/arch/um/kernel/ksyms.c b/arch/um/kernel/ksyms.c
index 836fc9b..0ae0dfc 100644
--- a/arch/um/kernel/ksyms.c
+++ b/arch/um/kernel/ksyms.c
@@ -58,6 +58,9 @@
 EXPORT_SYMBOL(os_rcv_fd);
 EXPORT_SYMBOL(run_helper);
 EXPORT_SYMBOL(start_thread);
+EXPORT_SYMBOL(os_major);
+EXPORT_SYMBOL(os_minor);
+EXPORT_SYMBOL(os_makedev);
 
 EXPORT_SYMBOL(add_sigio_fd);
 EXPORT_SYMBOL(ignore_sigio_fd);