crypto: caam - remove unused param of ctx_map_to_sec4_sg()

ctx_map_to_sec4_sg() function, added in
commit 045e3678

 ("crypto: caam - ahash hmac support")
has never used the "desc" parameter, so let's drop it.

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