GPRs and PC are 32-bit wide in loongarch32 mode.

Signed-off-by: Jiajie Chen <c@jia.je>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Song Gao <gaosong@loongson.cn>
Message-ID: <20230817093121.1053890-4-gaosong@loongson.cn>
[PMD: Rebased, set gdb_num_core_regs]
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230821125959.28666-9-philmd@linaro.org>