fs: crypto: support IV_INO_LBLK_32 for legacy (V1) format

New file encryption V2 format suports IV_INO_LBLK_32 but this is
needed in V1 to support over the air upgrade which uses
FS_ENCRYPTION_MODE_PRIVATE data encryption mode. Also randomness of
encrypted data for eMMC devices is fixed.

Test: vts-kernel-encryption test after Q to R update.

Change-Id: Idb9f5a140e755a9f5c9aa26d5f0e900252f441e8
Signed-off-by: Neeraj Soni <neersoni@codeaurora.org>