fs: xattr_handler table should be const

The entries in xattr handler table should be immutable (ie const)
like other operation tables.

Later patches convert common filesystems. Uncoverted filesystems
will still work, but will generate a compiler warning.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/mm/shmem.c b/mm/shmem.c
index eef4ebe..717aa62 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -2071,14 +2071,14 @@
 					  size, flags);
 }
 
-static struct xattr_handler shmem_xattr_security_handler = {
+static const struct xattr_handler shmem_xattr_security_handler = {
 	.prefix = XATTR_SECURITY_PREFIX,
 	.list   = shmem_xattr_security_list,
 	.get    = shmem_xattr_security_get,
 	.set    = shmem_xattr_security_set,
 };
 
-static struct xattr_handler *shmem_xattr_handlers[] = {
+static const struct xattr_handler *shmem_xattr_handlers[] = {
 	&generic_acl_access_handler,
 	&generic_acl_default_handler,
 	&shmem_xattr_security_handler,