lte: fix size in EpsNetworkFeatureSupport.c
We have to eat all the bytes, not only one.
Note: only one bit is supported from this "EPS network feature support", not sure how to properly deal with it, so let's keep the code as it is.
This commit was made because the MAGMA MME sends "EPS network feature support" to the UE in the NAS message "Attach Accept". OAI MME does not send this. So the bug about size was not seen.