drm/amd/powerplay: drop redundant smu call

smu_get_clk_info_from_vbios() was called repeatedly. It
seems a merge error.

Signed-off-by: Evan Quan <evan.quan@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>