add swap partition

Signed-off-by: Michel-FK <michel.stempin@funkey-project.com>

genimage.cfg

@@ -45,13 +45,21 @@ image sdcard.img {
 		partition-type = 0x83
 		bootable = "yes"
 		image = "FunKey/output/images/rootfs.ext4"
-		size = 100M
+		size = 100M # This will be resized to 1G during first boot
 	}
 
-#	partition share {
-#		offset = 1G
+# These partitions will be created during first boot
+#	partition swap {
+#		offset = 1.01G
 #		partition-type = 0xC
 #		bootable = "false"
-#		size = 0
+#		size = 128M
+#	}
+#
+#	partition share {
+#		offset = 1.138G
+#		partition-type = 0xC
+#		bootable = "false"
+#		size = 0 # Fill in the disk up to its full size
 #	}
 }