drm/amd/powerplay: fix the coverity warning about negative check for an unsigned value

There will be a coverity warning because min and max are both unsigned.

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>

drivers/gpu/drm/amd/powerplay/amdgpu_smu.c

@@ -214,9 +214,6 @@ int smu_set_soft_freq_range(struct smu_context *smu, enum smu_clk_type clk_type,
 {
 	int ret = 0;
 
-	if (min < 0 && max < 0)
-		return -EINVAL;
-
 	if (!smu_clk_dpm_is_enabled(smu, clk_type))
 		return 0;