crypto: convert drivers/crypto/* to use module_platform_driver()

This patch converts the drivers in drivers/crypto/* to use the
module_platform_driver() macro which makes the code smaller and a bit
simpler.

Cc: James Hsiao <jhsiao@amcc.com>
Cc: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Cc: Kim Phillips <kim.phillips@freescale.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Vladimir Zapolskiy <vzapolskiy@gmail.com>
Acked-by: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>