crypto: caam - dereferencing ERR_PTR on allocation failure

t_alg is an ERR_PTR here so we can't dereference it.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>