crypto: vmx - Fixing GHASH Key issue on little endian

GHASH table algorithm is using a big endian key.
In little endian machines key will be LE ordered.
After a lxvd2x instruction key is loaded as it is,
LE/BE order, in first case it'll generate a wrong
table resulting in wrong hashes from the algorithm.

Bug affects only LE machines.
In order to fix it we do a swap for loaded key.

Cc: stable@vger.kernel.org
Signed-off-by: Leonidas S Barbosa <leosilva@linux.vnet.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>