[Bug] 当打开RT_USING_DM时rt_hw_cpu_shutdown 重复定义

[BernardXiong]

RT-Thread Version

upstream

Hardware Type/Architectures

riscv

Develop Toolchain

GCC

Describe the bug

Issue: Multiple definition of rt_hw_cpu_shutdown when RT_USING_DM is enabled.

Description:
When the device manager feature is enabled (RT_USING_DM), both rt-thread/libcpu/risc-v/common64/cpuport.c and rt-thread/components/drivers/core/power.c define rt_hw_cpu_shutdown, causing a linker error.

Solution:
Make the rt_hw_cpu_shutdown function in cpuport.c weak using the rt_weak attribute. This allows the power management implementation to override the default cpuport implementation when device manager is enabled.

Other additional context

No response