drm/amdgpu: Check pmops for desired suspend state

[Why]
User might change the suspend behaviour from OS.

[How]
Check with pm for target suspend state and set s0ix
flag only for s2idle state.

v2: User might change default suspend state, use target state
v3: squash in build fix
Suggested-by: Lijo Lazar <Lijo.Lazar@amd.com>
Signed-off-by: Pratik Vishwakarma <Pratik.Vishwakarma@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c

@@ -26,6 +26,7 @@
 #include <linux/slab.h>
 #include <linux/power_supply.h>
 #include <linux/pm_runtime.h>
+#include <linux/suspend.h>
 #include <acpi/video.h>
 #include <acpi/actbl.h>
 
@@ -1042,7 +1043,7 @@ bool amdgpu_acpi_is_s0ix_supported(struct amdgpu_device *adev)
 #if defined(CONFIG_AMD_PMC) || defined(CONFIG_AMD_PMC_MODULE)
 	if (acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0) {
 		if (adev->flags & AMD_IS_APU)
-			return true;
+			return pm_suspend_target_state == PM_SUSPEND_TO_IDLE;
 	}
 #endif
 	return false;