drm/amd/display: Add KUnit tests for ism

Add KUnit coverage for the following ISM functions:

- dm_ism_next_state(): state transitions for running, busy,
  hysteresis-wait, optimized-idle, and aborted states
- dm_ism_get_sso_delay(): null stream, zero frames, 1080p60 3-frame,
  and 4k60 1-frame calculations
- dm_ism_get_idle_allow_delay(): null stream, zero filter/entry/delay
  frames, short-idle filtering, wrap-around, old history cutoff,
  mixed durations, and entry count exceeding history size
- amdgpu_dm_ism_init(): initial state setup
- amdgpu_dm_ism_fini(): cleanup after init
- dm_ism_set_last_idle_ts(): timestamp update
- dm_ism_insert_record(): basic insert and wrap-around
- dm_ism_trigger_event(): valid and invalid transitions

Assisted-by: Copilot:Claude-Opus-4.8
Reviewed-by: Bhawanpreet Lakha <bhawanpreet.lakha@amd.com>
Signed-off-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: George Zhang <george.zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

0 files changed, 0 insertions, 0 deletions