drm/amd/pm: fix the print_clk_levels issue for SMU v13.0.6

Pass the correct size to smu_v13_0_6_print_clks, otherwise
the same place in buf will be re-written.

Signed-off-by: Le Ma <le.ma@amd.com>
Reviewed-by: Lijo Lazar <lijo.lazar@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>