powerhint.json: correct the path and value Because the arch of sm7150 is different from 8150, correct the path and adjust the value to align with sm7150. This is the initial version of settings and still need to tuning for power/performance balance. Bug: 142552311 Test: build and check the values Change-Id: If061ee698c5f0164af876f171d504daa7a0c5847