drm/i915/gvt: Fix relocation of shadow bb

set_gma_to_bb_cmd() is completely bogus - it is (incorrectly) applying
the rules to read a GTT offset from a command as opposed to writing the
GTT offset. And to cap it all set_gma_to_bb_cmd() is called within a list
iterator of the most strange construction.

Fixes: be1da7070a ("drm/i915/gvt: vGPU command scanner")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Zhi Wang <zhi.a.wang@intel.com>
Cc: Yulei Zhang <yulei.zhang@intel.com>
Cc: <drm-intel-fixes@lists.freedesktop.org> # v4.10-rc1+
Tested-by: Tina Zhang <tina.zhang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

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

@@ -113,7 +113,7 @@ struct intel_shadow_bb_entry {
 	struct drm_i915_gem_object *obj;
 	void *va;
 	unsigned long len;
-	void *bb_start_cmd_va;
+	u32 *bb_start_cmd_va;
 };
 
 #define workload_q_head(vgpu, ring_id) \