amdgpu/pm: Optimize emit_clock_levels for arcturus - part 2

 Use variables to remove ternary expression in print statement and
 improve readability. This will help to optimize the code duplication
 in the switch statement
 Also Changed:
  replaced single_dpm_table->count as iterator in for loops with safer
    clocks_num_levels value
  replaced dpm_table.value usage with local var clocks_mhz

Signed-off-by: Darren Powell <darren.powell@amd.com>
Reviewed-by: Lijo Lazar <lijo.lazar@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>