make fs/{namespace,super}.c forget about acct.h

These externs belong in fs/internal.h.  Rename (they are not acct-specific
anymore) and move them over there.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/internal.h b/fs/internal.h
index 9a2edba..e325b4f 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -143,3 +143,9 @@
  * pipe.c
  */
 extern const struct file_operations pipefifo_fops;
+
+/*
+ * fs_pin.c
+ */
+extern void sb_pin_kill(struct super_block *sb);
+extern void mnt_pin_kill(struct mount *m);