Doubly linked list

Revision:
0:a76236b7a8e6
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed-os.lib	Mon Sep 16 13:57:00 2019 +0000
@@ -0,0 +1,1 @@
+https://github.com/ARMmbed/mbed-os/#5941d1718339116cd12914238ec331c84da3d08f