[model-converter] switch from assert() to CHECK() (no sense to continue if any of these checks fail)
[model-converter] switch from assert() to CHECK() (no sense to continue if any of these checks fail)

hpi-xnor/BMXNet,hpi-xnor/BMXNet,hpi-xnor/BMXNet,hpi-xnor/BMXNet,hpi-xnor/BMXNet,hpi-xnor/BMXNet,hpi-xnor/BMXNet,hpi-xnor/BMXNet,hpi-xnor/BMXNet