Missing malloc.h and clock_id_t were causing issues to build.
It was tested with this configuration:
- linux ubuntu 14.04.5
- arduino-mega2560 board
- avr-libc-1.8.0-4.1
This change was needed to build iotivity example
Bug: https://github.com/RIOT-OS/RIOT/issues/6241
Change-Id: I82ce246093b3467dfe9746f999bcc9335dbb65f6
Signed-off-by: Philippe Coval <philippe.coval@osg.samsung.com>