target/riscv: rvv: Provide group continuous ld/st flow for unit-stride ld/st instructions

target/riscv: rvv: Provide group continuous ld/st flow for unit-stride ld/st instructions

The vector unmasked unit-stride and whole register load/store
instructions will load/store continuous memory. If the endian of both
the host and guest architecture are the same, then we can group the
element load/store to load/store more data at a time.

Signed-off-by: Max Chou <max.chou@sifive.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-ID: <20240918171412.150107-7-max.chou@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>