coda: fix creds reference

Needs a header file for credentials struct:

linux-next-20081023/fs/coda/file.c:177: error: dereferencing pointer to incomplete type
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Cc: Jan Harkes <jaharkes@cs.cmu.edu>
Cc: David Howells <dhowells@redhat.com>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NJames Morris <jmorris@namei.org>

fs/coda/file.c

@@ -13,6 +13,7 @@
 #include <linux/file.h>
 #include <linux/fs.h>
 #include <linux/stat.h>
+#include <linux/cred.h>
 #include <linux/errno.h>
 #include <linux/smp_lock.h>
 #include <linux/string.h>