super: set a prop after symlinks are created

This allows actions to be triggered once the super partitions
are available.

This is helpful when adjustments need to be made to the
device ramdisk based on the installed system.

Change-Id: I980d8ed481356dc75ce2fa99ae8d60e7c704eb86
(cherry picked from commit 88c6e654d3a4a97b7e3a4da900ea3e1ad4dc4e1a)
diff --git a/partitionmanager.cpp b/partitionmanager.cpp
index f44544d..305472e 100755
--- a/partitionmanager.cpp
+++ b/partitionmanager.cpp
@@ -3413,6 +3413,7 @@
 	if (access(("/dev/block/bootdevice/by-name/" + bare_partition_name).c_str(), F_OK) == -1) {
 		LOGINFO("Symlinking %s => /dev/block/bootdevice/by-name/%s \n", fstabEntry.blk_device.c_str(), bare_partition_name.c_str());
 		symlink(fstabEntry.blk_device.c_str(), ("/dev/block/bootdevice/by-name/" + bare_partition_name).c_str());
+		property_set("twrp.super.symlinks_created", "true");
 	}
 
     return true;