eCryptfs: fix error handling in ecryptfs_init

ecryptfs_init() exits without doing any cleanup jobs if
ecryptfs_init_messaging() fails.  In that case, eCryptfs leaves
sysfs entries, leaks memory, and causes an invalid page fault.
This patch fixes the problem.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Acked-by: Michael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>