Function mbedtls_oid_get_oid_by_ec_grp_algid 

pub unsafe extern "C" fn mbedtls_oid_get_oid_by_ec_grp_algid(
    grp_id: mbedtls_ecp_group_id,
    oid: *mut *const c_char,
    olen: *mut usize,
) -> c_int

\brief Translate EC group identifier into AlgorithmIdentifier OID, for curves that are directly encoded at this level

\param grp_id EC group identifier \param oid place to store ASN.1 OID string pointer \param olen length of the OID

\return 0 if successful, or MBEDTLS_ERR_OID_NOT_FOUND