For the people who are wanting to build a Yocto image of the NXP Modular Gateway using Ubuntu 16.04, there is some changes needed:
Due to Ubuntu 16.04 not natively having libsdl, some changes to the conf/local.conf needs to be made to tell bitbake that qeum needs to be sources and compiled.
To do this, comment out/remove the following lines in conf/local.conf in your build folder:
PACKAGECONFIG_append_pn-qemu-native = " sdl"
PACKAGECONFIG_append_pn-nativesdk-qemu = " sdl"
ASSUME_PROVIDED += "libsdl-native"