hw/char: riscv_htif: Use conventional 's' for HTIFState

hw/char: riscv_htif: Use conventional 's' for HTIFState

QEMU source codes tend to use 's' to represent the hardware state.
Let's use it for HTIFState.

Signed-off-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20221229091828.1945072-5-bmeng@tinylab.org>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>