monitor/hmp-cmds-target: add CPU_DUMP_VPU in hmp_info_registers()

monitor/hmp-cmds-target: add CPU_DUMP_VPU in hmp_info_registers()

Commit b84694defb added the CPU_DUMP_VPU to allow vector registers to be
logged by log_cpu_exec() in TCG. This flag was then used in commit
b227f6a8a7 to print RISC-V vector registers using this flag. Note that
this change was done in riscv_cpu_dump_state(), the cpu_dump_state()
callback for RISC-V, the same callback used in hmp_info_registers().

Back then we forgot to change hmp_info_registers(), and 'info registers'
isn't showing RISC-V vector registers as a result. No other target is
impacted since only RISC-V is using CPU_DUMP_VPU.

There's no reason to not show VPU regs in info_registers(), so add
CPU_DUMP_VPU to hmp_info_registers(). This will print vector registers
for all RISC-V machines and, as said above, has no impact in other
archs.

Cc: Dr. David Alan Gilbert <dave@treblig.org>
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20250623145306.991562-1-dbarboza@ventanamicro.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>