Suspend to RAM cause screen to glitch on navi10

Submitted by yshui @yshui

Assigned to Default DRI bug account

Link to original bug (#111846)

Description

To reproduce:

1. have two monitors (not sure if necessary, also the two monitors i have have different resolutions)
   
2. suspend computer to ram
   
3. wake up computer
   
4. screen flickers
   

Observation:

1. set pp_dpm_mclk immediately fix the problem
2. after step 1, set power_dpm_force_performance_level to "auto", then the problem reappears.
3. flicker doesn't occur on vconsole

Software Versions:

This bug occurs on linux 5.3.0, xorg 1.20.5, mesa 19.3.0 40087ffc5b9