drm/i915/gvt: stop using drm_edid_block_valid()

We'll want to stop drm_edid_block_valid() usage. KVMGT is the last
user. Replace with drm_edid_valid(), which unfortunately requires an
allocated drm_edid. However, on the plus side, this would be required to
handle the TODO comment about EDID extension block support.
Acked-by: Zhi Wang <zhiwang@kernel.rog>
Reviewed-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240812142849.1588006-1-jani.nikula@intel.comSigned-off-by: Jani Nikula <jani.nikula@intel.com>

drivers/gpu/drm/i915/gvt/kvmgt.c

@@ -425,6 +425,18 @@ static const struct intel_vgpu_regops intel_vgpu_regops_opregion = {
 	.release = intel_vgpu_reg_release_opregion,
 };
 
+static bool edid_valid(const void *edid, size_t size)
+{
+	const struct drm_edid *drm_edid;
+	bool is_valid;
+
+	drm_edid = drm_edid_alloc(edid, size);
+	is_valid = drm_edid_valid(drm_edid);
+	drm_edid_free(drm_edid);
+
+	return is_valid;
+}
+
 static int handle_edid_regs(struct intel_vgpu *vgpu,
 			struct vfio_edid_region *region, char *buf,
 			size_t count, u16 offset, bool is_write)
@@ -443,11 +455,7 @@ static int handle_edid_regs(struct intel_vgpu *vgpu,
 		switch (offset) {
 		case offsetof(struct vfio_region_gfx_edid, link_state):
 			if (data == VFIO_DEVICE_GFX_LINK_STATE_UP) {
-				if (!drm_edid_block_valid(
-					(u8 *)region->edid_blob,
-					0,
-					true,
-					NULL)) {
+				if (!edid_valid(region->edid_blob, EDID_SIZE)) {
 					gvt_vgpu_err("invalid EDID blob\n");
 					return -EINVAL;
 				}