drm/amd/pm: Don't clear SI SMC table when setting power limit

drm/amd/pm: Don't clear SI SMC table when setting power limit

[ Upstream commit d5077426e1a76d269e518e048bde2e9fc49b32ad ]

There is no reason to clear the SMC table.
We also don't need to recalculate the power limit then.

Fixes: 841686df9f7d ("drm/amdgpu: add SI DPM support (v4)")
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit e214d626253f5b180db10dedab161b7caa41f5e9)
Signed-off-by: Sasha Levin <sashal@kernel.org>