hw/riscv/virt-acpi-build.c: Update the HID of RISC-V UART

hw/riscv/virt-acpi-build.c: Update the HID of RISC-V UART

The requirement ACPI_060 in the RISC-V BRS specification [1], requires
NS16550 compatible UART to have the HID RSCV0003. So, update the HID for
the UART.

[1] -  https://github.com/riscv-non-isa/riscv-brs/releases/download/v0.0.2/riscv-brs-spec.pdf
       (Chapter 6)

Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Message-Id: <20240716144306.2432257-3-sunilvl@ventanamicro.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>