[PATCH] Introduce vfs_listxattr

This patch moves code out of fs/xattr.c:listxattr into a new function -
vfs_listxattr. The code for vfs_listxattr was originally submitted by Bill
Nottingham <notting@redhat.com> to Unionfs.

Sorry about that.  The reason for this submission is to make the
listxattr code in fs/xattr.c a little cleaner (as well as to clean up
some code in Unionfs.)

Currently, Unionfs has vfs_listxattr defined in its code.  I think
that's very ugly, and I'd like to see it (re)moved.  The logical place
to put it, is along side of all the other vfs_*xattr functions.

Overall, I think this patch is benefitial for both kernel.org kernel and
Unionfs.

Signed-off-by: Josef "Jeff" Sipek <jsipek@cs.sunysb.edu>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>