ubifs: mount fails after power cycle

When kernel uses file system encryption, fscrypt on UBIFS v5,
after a hard power cycle UBIFS journal replay fails which results in mount failure.

Failure logs:
UBIFS: recovery needed
UBIFS error (pid 0): ubifs_validate_entry: bad directory entry node
UBIFS error (pid 0): replay_bud: bad node is at LEB 890:24576
UBIFS error (pid 0): ubifs_mount: Error reading superblock on volume 'ubi0:rootfs' errno=-22!

This change is ported from kernel:
commit id: 304790c038bc4af4f19774705409db27eafb09fc

Kernel commit description:
    Kernel commit description:
    ubifs: Relax checks in ubifs_validate_entry()

    With encrypted filenames we store raw binary data, doing
    string tests is no longer possible.

Signed-off-by: rminnikanti <rminnikanti@marvell.com>
Reviewed-by: Heiko Schocher <hs@denx.de>