drm/amd/powerpaly: fix navi series custom peak level value error

fix other navi asic set peak performance level error.
because the navi10_ppt.c will handle navi12 14 asic,
it will use navi10 peak value to set other asic, it is not correct.

after patch:
only navi10 use custom peak value, other asic will used default value.

Signed-off-by: Kevin Wang <kevin1.wang@amd.com>
Reviewed-by: Evan Quan <evan.quan@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>