drm/amdgpu: use the new drm_exec object for CS v3

Use the new component here as well and remove the old handling.

v2: drop dupplicate handling
v3: fix memory leak pointed out by Tatsuyuki

Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230711133122.3710-7-christian.koenig@amd.com