operational SPI with OS5

Revision:
65:caf630d9c605
Parent:
64:7091d1363acd
--- a/mbed-os.lib	Wed Apr 11 08:15:02 2018 +0100
+++ b/mbed-os.lib	Wed May 02 06:30:02 2018 +0100
@@ -1,1 +1,1 @@
-https://github.com/ARMmbed/mbed-os/#f9ee4e849f8cbd64f1ec5fdd4ad256585a208360
+https://github.com/ARMmbed/mbed-os/#c05d72c3c005fbb7e92c3994c32bda45218ae7fe