This commit enables more slots so that the "real UE" preprocessor can
schedule them. The DL phytest preprocessor continues to only schedule
slots 1 & 3.  This is because the OAI-UE needs to have PUCCH scheduled
at least six slots in advance.  Since we do not support this (yet), but
assume that two slots are enough, we schedule the UE only in slot 1 & 3
so it has 6 slots until slot 7 to send PUCCH.