drm/amdkfd: Avoid hanging hardware in stop_cpsch

Don't use the HWS if it's known to be hanging. In a reset also
don't try to destroy the HIQ because that may hang on SRIOV if the
KIQ is unresponsive.

Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Tested-by: Emily Deng <Emily.Deng@amd.com>
Reviewed-by: shaoyunl <shaoyun.liu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>