api_storage: Fix non-first storage device enumeration

When enabling CONFIG_API and chain-loading GRUB2 on jetson-tk1, only the
eMMC would show up as (hd0), but not the SD card, leading to GRUB not
finding its configuration and modules, falling back to a rescue shell.

This is because enum_ended would get set for !more after returning a
cookie for the first MMC device in group 3.

Fix this by properly setting the "more" argument also in the case of the
first storage device of a group.

Signed-off-by: Andreas Färber <afaerber@suse.de>

api/api_storage.c

@@ -112,6 +112,11 @@ static int dev_stor_get(int type, int first, int *more, struct device_info *di)
 		else
 			found = 1;
 
+		/* provide hint if there are more devices in
+		 * this group to enumerate */
+		if (1 < specs[type].max_dev)
+			*more = 1;
+
 	} else {
 		for (i = 0; i < specs[type].max_dev; i++)
 			if (di->cookie == (void *)get_dev(specs[type].name, i)) {