Even though I introduced cell object in 79370ebf (software/ors-amarisoft:
enb.jinja2.cfg: Stop using C Preprocessor and switch to Jinja2 completely) it
is currently only cell.bandwidth that is living there, while all other cell
parameters are still fetched from slapparameter_dict directly.

We will soon introduce cell variable - that will iterate over cell_dict, and
also keeping global cell won't work due to name shadowing. On the other hand we
are not yet ready to start migrating all cell parameters to be accessible via
cell object.

-> So inline code for lte bandwidth parameter until the time comes to rework
all cell parameters to be accessible via cell object.

Rendered enb.cfg and gnb.cfg stay the same.