crypto: caam - remove deadcode on 32-bit platforms

When building on a platform with a 32bit DMA address, taking the
upper 32 bits makes no sense.

Signed-off-by: Franck LENORMAND <franck.lenormand@nxp.com>
Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>