drm/i915/gt: Fix NULL deref on sched_engine alloc failure

In the Linux kernel, the following vulnerability has been resolved: drm/i915/gt: Fix NULL deref on sched_engine alloc failure Avoid using intel_context_put() before intel_context_init() in execlists_create_virtual() as the kref_put() inside would lead to NULL deref on the IOCTL path when sched_engine allocation fails. Discovered using AI-assisted static analysis confirmed by Intel Product Security. (cherry picked from commit 4f2a12f2d50e9f48227656e4dcbd6423506be31d)

Where it's fixed