rpmsg: Change naming of mediatek rpmsg property

Change from "mtk,rpmsg-name" to "mediatek,rpmsg-name" to sync with the
vendor name defined in vendor-prefixes.yaml.

Signed-off-by: Tinghan Shen <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
[Fixed capital letter in title]
Signed-off-by: Mathieu Poirier <[e-mail]>
Signed-off-by: Bjorn Andersson <[e-mail]>

drivers/rpmsg/mtk_rpmsg.c

···
 	int ret;
 
 	for_each_available_child_of_node(node, child) {
-		ret = of_property_read_string(child, "mtk,rpmsg-name", &name);
+		ret = of_property_read_string(child, "mediatek,rpmsg-name", &name);
 		if (ret)
 			continue;