drm/amd/powerplay: correct SW smu11 thermal range settings

Problems with current settings:
1. The min value was overrided to 0 on Vega20 & Navi10. While
   the expected should be -273.15 C.
2. The thermal min/max threshold was output in wrong unit on
   Navi10 & Arcturus. As TEMP_RANGE_MIN/MAX is already in
   millicelsius. And "*1000" in smu_v11_0_start_thermal_control
   makes the output wrongly.

Signed-off-by: Evan Quan <evan.quan@amd.com>
Reviewed-by: Kenneth Feng <kenneth.feng@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>