include/uapi/linux: Fix indentation in kfd_smi_event enum

Replace spaces with Tabs to fix indentation in kfd_smi_event
enum.
Signed-off-by: Mukul Joshi <mukul.joshi@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>