Ports serie USB trensparent

Revision:
0:0184b799af90
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed-os.lib	Wed May 18 07:48:25 2022 +0000
@@ -0,0 +1,1 @@
+https://github.com/ARMmbed/mbed-os/#cf4f12a123c05fcae83fc56d76442015cb8a39e9