drm/amd: Disallow s0ix without BIOS support again

drm/amd: Disallow s0ix without BIOS support again

commit cf488dcd0ab7 ("drm/amd: Allow s0ix without BIOS support") showed
improvements to power consumption over suspend when s0ix wasn't enabled in
BIOS and the system didn't support S3.

This patch however was misguided because the reason the system didn't
support S3 was because SMT was disabled in OEM BIOS setup.
This prevented the BIOS from allowing S3.

Also allowing GPUs to use the s2idle path actually causes problems if
they're invoked on systems that may not support s2idle in the platform
firmware. `systemd` has a tendency to try to use `s2idle` if `deep` fails
for any reason, which could lead to unexpected flows.

The original commit also fixed a problem during resume from suspend to idle
without hardware support, but this is no longer necessary with commit
ca4751866397 ("drm/amd: Don't allow s0ix on APUs older than Raven")

Revert commit cf488dcd0ab7 ("drm/amd: Allow s0ix without BIOS support")
to make it match the expected behavior again.

Cc: Rafael Ávila de Espíndola <rafael@espindo.la>
Link: https://github.com/torvalds/linux/blob/v6.1/drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c#L1060
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/2599
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>