crypto: Fix HMAC failure

HMAC operation for small and large packets are failing.
This is due to 2 reason:
- Packet size set for each operation is larger than what is
  supported by the BAM hardware.
- Byte count value read after the end of the operation is of
  incorrect  byte order.
Fix is to decrease the max packet to the  max of (32KB-64) and
fix byte order when storing the byte count value from the register
dump of the results at the end of the operation.

Change-Id: Ieb91ab2ad22cb8a08a575c058b7178e532bea7d7
Signed-off-by: Mona Hossain <mhossain@codeaurora.org>