riscv: Provide vector crypto implementation of AES-ECB mode.

riscv: Provide vector crypto implementation of AES-ECB mode.

This patch provides stream and multi-block implementations for
AES-128-ECB, AES-192-ECB, and AES-256-ECB to accelerate AES-ECB.
Also, refactor functions to share the same variable
declaration in aes-riscv64-zvkned.pl.

Signed-off-by: Phoebe Chen <phoebe.chen@sifive.com>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
Reviewed-by: Paul Dale <pauli@openssl.org>
Reviewed-by: Hugo Landau <hlandau@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/21923)