drm/i915: remove intel_vgpu::intx_trigger

intel_vgpu::intx_trigger was never used since its addition in commit
f30437c5 (drm/i915/gvt: add KVMGT support). Drop it.

Found by https://github.com/jirislaby/clang-struct.
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: intel-gfx@lists.freedesktop.org
Acked-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240216065326.6910-15-jirislaby@kernel.org

drivers/gpu/drm/i915/gvt/gvt.h

@@ -221,7 +221,6 @@ struct intel_vgpu {
 
 	struct vfio_region *region;
 	int num_regions;
-	struct eventfd_ctx *intx_trigger;
 	struct eventfd_ctx *msi_trigger;
 
 	/*