crypto: aesni_intel - improve lrw and xts performance by utilizing parallel AES-NI hardware pipelines

Use parallel LRW and XTS encryption facilities to better utilize AES-NI
hardware pipelines and gain extra performance.

Tcrypt benchmark results (async), old vs new ratios:

Intel Core i5-2450M CPU (fam: 6, model: 42, step: 7)

aes:128bit
        lrw:256bit      xts:256bit
size    lrw-enc lrw-dec xts-dec xts-dec
16B     0.99x   1.00x   1.22x   1.19x
64B     1.38x   1.50x   1.58x   1.61x
256B    2.04x   2.02x   2.27x   2.29x
1024B   2.56x   2.54x   2.89x   2.92x
8192B   2.85x   2.99x   3.40x   3.23x

aes:192bit
        lrw:320bit      xts:384bit
size    lrw-enc lrw-dec xts-dec xts-dec
16B     1.08x   1.08x   1.16x   1.17x
64B     1.48x   1.54x   1.59x   1.65x
256B    2.18x   2.17x   2.29x   2.28x
1024B   2.67x   2.67x   2.87x   3.05x
8192B   2.93x   2.84x   3.28x   3.33x

aes:256bit
        lrw:348bit      xts:512bit
size    lrw-enc lrw-dec xts-dec xts-dec
16B     1.07x   1.07x   1.18x   1.19x
64B     1.56x   1.56x   1.70x   1.71x
256B    2.22x   2.24x   2.46x   2.46x
1024B   2.76x   2.77x   3.13x   3.05x
8192B   2.99x   3.05x   3.40x   3.30x

Cc: Huang Ying <ying.huang@intel.com>
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Reviewed-by: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>