drm/i915/gem: Flush lmem contents after construction

i915_gem_object_create_lmem_from_data() lacks the flush of the data
written to lmem to ensure the object is marked as dirty and the writes
flushed to the backing store. Once created, we can immediately release
the obj->mm.mapping caching of the vmap.

Fixes: 7acbbc7c ("drm/i915/guc: put all guc objects in lmem when available")
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Andi Shyti <andi.shyti@linux.intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Signed-off-by: Chris Wilson <chris.p.wilson@linux.intel.com>
Cc: <stable@vger.kernel.org> # v5.16+
Signed-off-by: Nirmoy Das <nirmoy.das@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Reviewed-by: Nirmoy Das <nirmoy.das@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230316165918.13074-1-nirmoy.das@intel.com

drivers/gpu/drm/i915/gem/i915_gem_lmem.c

@@ -127,7 +127,8 @@ i915_gem_object_create_lmem_from_data(struct drm_i915_private *i915,
 
 	memcpy(map, data, size);
 
-	i915_gem_object_unpin_map(obj);
+	i915_gem_object_flush_map(obj);
+	__i915_gem_object_release_map(obj);
 
 	return obj;
 }