drm/amd/powerplay: avoid DPM reenable process on Navi1x ASICs V2

Otherwise, without RLC reinitialization, the DPM reenablement
will fail. That affects the custom pptable uploading.

V2: setting/clearing uploading_custom_pp_table in
    smu_sys_set_pp_table()

Reported-by: Matt Coffin <mcoffin13@gmail.com>
Signed-off-by: Evan Quan <evan.quan@amd.com>
Tested-by: Matt Coffin <mcoffin13@gmail.com>
Reviewed-by: Kenneth Feng <kenneth.feng@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>