Suga koubou / Mbed 2 deprecated usbhost_midi

see https://os.mbed.com/users/okini3939/notebook/USBHostMIDI/

Dependencies:   USBHost mbed

Diff: mbed.bld

Revision:
0:0fd787d62a99
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed.bld	Wed Jan 03 08:07:31 2018 +0000
@@ -0,0 +1,1 @@
+http://mbed.org/users/mbed_official/code/mbed/builds/e7ca05fa8600
\ No newline at end of file