dm/amd/pm: Fix problems with reboot/shutdown for some SMU 13.0.4/13.0.11 users

Limit the workaround introduced by commit 31729e8c ("drm/amd/pm: fixes
a random hang in S4 for SMU v13.0.4/11") to only run in the s4 path.

Cc: Tim Huang <Tim.Huang@amd.com>
Fixes: 31729e8c

 ("drm/amd/pm: fixes a random hang in S4 for SMU v13.0.4/11")
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3351
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>