amdgpu_pp_ip_funcs is introduced to handle the two code paths,
the legacy one and the new powerplay implementation.

CONFIG_DRM_AMD_POWERPLAY kernel configuration option is
introduced for the powerplay component.

v4: squash in fixes
v3: register debugfs file when powerplay module enable
v2: add amdgpu_ucode_init_bo in hw init when amdgpu_powerplay enable.
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Signed-off-by: Jammy Zhou <Jammy.Zhou@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>