crypto: caam - Fix kerneldoc

Fix kerneldoc warnings like:

  drivers/crypto/caam/caamalg_qi2.c:73: warning: cannot understand function prototype: 'struct caam_ctx'
  drivers/crypto/caam/caamalg_qi2.c:2962: warning: cannot understand function prototype: 'struct caam_hash_ctx'
  drivers/crypto/caam/ctrl.c:449: warning: Function parameter or member 'ctrl' not described in 'caam_get_era'

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Iuliana Prodan <iuliana.prodan@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>