Add fs/namespace.c to the filesystems api-summary docbook.

Signed-off-by: Randy Dunlap <redacted>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
---
 Documentation/filesystems/api-summary.rst |    3 +++
 1 file changed, 3 insertions(+)

--- linux-next-20210317.orig/Documentation/filesystems/api-summary.rst
+++ linux-next-20210317/Documentation/filesystems/api-summary.rst

@@ -101,6 +101,9 @@ Other Functions
 .. kernel-doc:: fs/xattr.c
    :export:
 
+.. kernel-doc:: fs/namespace.c
+   :export:
+
 The proc filesystem
 ===================