drm/ttm: Make ttm_bo_init_validate safe against ttm_operation_ctx re-ordering

drm/ttm: Make ttm_bo_init_validate safe against ttm_operation_ctx re-ordering

Struct ttm_operation_ctx initializer in ttm_bo_init_validate assumes the
order of the structure fields when it is configuring the interruptible
flag.

Fix it by using named initialization.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
Acked-by: Thadeu Lima de Souza Cascardo <cascardo@igalia.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Tvrtko Ursulin <tursulin@ursulin.net>
Link: https://lore.kernel.org/r/20250919131530.91247-2-tvrtko.ursulin@igalia.com