Add additional check to verify dentry is hashed after vfs_mkdir() is successful. Bug: 148423333 Test: kernel seftest - incfs_test, manual test removing .index when mounted Signed-off-by: Akilesh Kailash <akailash@google.com> Change-Id: I7d2d71d480db4f02b7f3a347b5734c6643843594