before this change, the pp_feature sysfs show feature enable state by
logic feature id, it is not easy to read.
this change will sort pp_features show index by asic feature id.

before:
features high: 0x00000623 low: 0xb3cdaffb
00. DPM_PREFETCHER       ( 0) : enabeld
01. DPM_GFXCLK           ( 1) : enabeld
02. DPM_UCLK             ( 3) : enabeld
03. DPM_SOCCLK           ( 4) : enabeld
04. DPM_MP0CLK           ( 5) : enabeld
05. DPM_LINK             ( 6) : enabeld
06. DPM_DCEFCLK          ( 7) : enabeld
07. DS_GFXCLK            (10) : enabeld
08. DS_SOCCLK            (11) : enabeld
09. DS_LCLK              (12) : disabled
10. PPT                  (23) : enabeld
11. TDC                  (24) : enabeld
12. THERMAL              (33) : enabeld
13. RM                   (35) : disabled
......

after:
features high: 0x00000623 low: 0xb3cdaffb
00. DPM_PREFETCHER       ( 0) : enabeld
01. DPM_GFXCLK           ( 1) : enabeld
02. DPM_GFX_PACE         ( 2) : disabled
03. DPM_UCLK             ( 3) : enabeld
04. DPM_SOCCLK           ( 4) : enabeld
05. DPM_MP0CLK           ( 5) : enabeld
06. DPM_LINK             ( 6) : enabeld
07. DPM_DCEFCLK          ( 7) : enabeld
08. MEM_VDDCI_SCALING    ( 8) : enabeld
09. MEM_MVDD_SCALING     ( 9) : enabeld
10. DS_GFXCLK            (10) : enabeld
11. DS_SOCCLK            (11) : enabeld
12. DS_LCLK              (12) : disabled
13. DS_DCEFCLK           (13) : enabeld
......
Signed-off-by: Kevin Wang <kevin1.wang@amd.com>
Reviewed-by: Kenneth Feng <kenneth.feng@amd.com>
Reviewed-by: Evan Quan <evan.quan@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>