travis: Build urandom native module in coverage job.
travis: Build urandom native module in coverage job.

tobbad/micropython,selste/micropython,trezor/micropython,MrSurly/micropython,kerneltask/micropython,MrSurly/micropython,adafruit/circuitpython,bvernoux/micropython,pozetroninc/micropython,pozetroninc/micropython,trezor/micropython,bvernoux/micropython,henriknelson/micropython,pozetroninc/micropython,adafruit/circuitpython,tobbad/micropython,trezor/micropython,bvernoux/micropython,MrSurly/micropython,trezor/micropython,henriknelson/micropython,selste/micropython,tobbad/micropython,trezor/micropython,kerneltask/micropython,adafruit/circuitpython,pramasoul/micropython,pozetroninc/micropython,henriknelson/micropython,adafruit/circuitpython,henriknelson/micropython,selste/micropython,pramasoul/micropython,kerneltask/micropython,tobbad/micropython,bvernoux/micropython,pozetroninc/micropython,tobbad/micropython,adafruit/circuitpython,pramasoul/micropython,selste/micropython,MrSurly/micropython,adafruit/circuitpython,bvernoux/micropython,pramasoul/micropython,henriknelson/micropython,kerneltask/micropython,MrSurly/micropython,kerneltask/micropython,selste/micropython,pramasoul/micropython