drm/amd: Warn users about potential s0ix problems

drm/amd: Warn users about potential s0ix problems

[ Upstream commit a6ed2035878e5ad2e43ed175d8812ac9399d6c40 ]

On some OEM setups users can configure the BIOS for S3 or S2idle.
When configured to S3 users can still choose 's2idle' in the kernel by
using `/sys/power/mem_sleep`.  Before commit 6dc8265f9803 ("drm/amdgpu:
always reset the asic in suspend (v2)"), the GPU would crash.  Now when
configured this way, the system should resume but will use more power.

As such, adjust the `amdpu_acpi_is_s0ix function` to warn users about
potential power consumption issues during their first attempt at
suspending.

Reported-by: Bjoren Dasse <bjoern.daase@gmail.com>
Link: https://gitlab.freedesktop.org/drm/amd/-/issues/1824
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>