crypto: caam - fix DMA mapping xcbc key twice

Fix a side effect of adding xcbc support, which leads to DMA mapping the
key twice.

Fixes: 12b8567 ("crypto: caam - add support for xcbc(aes)")
Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/caam/caamhash.c

@@ -1897,8 +1897,7 @@ static int caam_hash_cra_init(struct crypto_tfm *tfm)
 	}
 
 	dma_addr = dma_map_single_attrs(ctx->jrdev, ctx->sh_desc_update,
-					offsetof(struct caam_hash_ctx,
-						 sh_desc_update_dma),
+					offsetof(struct caam_hash_ctx, key),
 					ctx->dir, DMA_ATTR_SKIP_CPU_SYNC);
 	if (dma_mapping_error(ctx->jrdev, dma_addr)) {
 		dev_err(ctx->jrdev, "unable to map shared descriptors\n");