target/riscv: Add vill check for whole vector register move instructions

target/riscv: Add vill check for whole vector register move instructions

The ratified version of RISC-V V spec section 16.6 says that
`The instructions operate as if EEW=SEW`.

So the whole vector register move instructions depend on the vtype
register that means the whole vector register move instructions should
raise an illegal-instruction exception when vtype.vill=1.

Signed-off-by: Max Chou <max.chou@sifive.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-ID: <20231129170400.21251-2-max.chou@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>