[OLK-5.10] Add support for turning off Zhaoxin ahci controller runtime pm from sysfs · Pull Request !548 · openEuler/kernel

There exits some problems with enabling ahci controller runtime pm on various Zhaoxin platforms.
    
For some Zhaoxin CPUs, link into listen mode, and PHY into P2, which will cause the device to continuously send comminit. When the controller is in D3, the comminit will continuously wake up the controller, resulting in the controller being unable to stabilize at D3;

For another Zhaoxin CPUs, after entering and exiting runtime pm for a certain number of times, ahci controller reset accumulates for many times, which will make ahci and PXPTRF P2CW think that the other party can no longer receive requests and block the P2CW path, resulting in failure to recognize the device;

In addition, there are some other Zhaoxin CPUs , the test is normal, but considering that the server platform is not sensitive to power consumption, and this part has very little impact on power consumption;

In summary, it is recommended to close the zx ahci controller runtime pm.

### Issue
https://gitee.com/openeuler/kernel/issues/I6SL79

### Knowe Issue
NA

### Default config change
NA

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