mtd: mtdpart: Don't create platform device that'll never probe

These "nvmem-cells" platform devices never get probed because there's no
platform driver for it and it's never used anywhere else. So it's a
waste of memory. These devices also cause fw_devlink to block nvmem
consumers of "nvmem-cells" partition from probing because the supplier
device never probes.

So stop creating platform devices for nvmem-cells partitions to avoid
wasting memory and to avoid blocking probing of consumers.
Reported-by: NMaxim Kiselev <bigunclemax@gmail.com>
Fixes: bcdf0315 ("mtd: call of_platform_populate() for MTD partitions")
Signed-off-by: NSaravana Kannan <saravanak@google.com>
Tested-by: NMaksim Kiselev <bigunclemax@gmail.com>
Tested-by: NDouglas Anderson <dianders@chromium.org>
Tested-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Luca Weiss <luca.weiss@fairphone.com> # qcom/sm7225-fairphone-fp4
Link: https://lore.kernel.org/r/20230207014207.1678715-13-saravanak@google.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/mtd/mtdpart.c

@@ -577,6 +577,7 @@ static int mtd_part_of_parse(struct mtd_info *master,
 {
 	struct mtd_part_parser *parser;
 	struct device_node *np;
+	struct device_node *child;
 	struct property *prop;
 	struct device *dev;
 	const char *compat;
@@ -594,6 +595,15 @@ static int mtd_part_of_parse(struct mtd_info *master,
 	else
 		np = of_get_child_by_name(np, "partitions");
 
+	/*
+	 * Don't create devices that are added to a bus but will never get
+	 * probed. That'll cause fw_devlink to block probing of consumers of
+	 * this partition until the partition device is probed.
+	 */
+	for_each_child_of_node(np, child)
+		if (of_device_is_compatible(child, "nvmem-cells"))
+			of_node_set_flag(child, OF_POPULATED);
+
 	of_property_for_each_string(np, "compatible", prop, compat) {
 		parser = mtd_part_get_compatible_parser(compat);
 		if (!parser)