drm/amd/powerplay: fix pre-check condition for setting clock range

This fix will handle some MP1 FW issue like as mclk dpm table in renoir has a reverse
dpm clock layout and a zero frequency dpm level as following case.

cat pp_dpm_mclk
0: 1200Mhz
1: 1200Mhz
2: 800Mhz
3: 0Mhz

Signed-off-by: Prike Liang <Prike.Liang@amd.com>
Reviewed-by: Evan Quan <evan.quan@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>