... so if we want to have 1 BWP configured at any given time we need to
reconfigure BWP 1 every time. This means that since the gNB has more
than 1 BWPs (for use for different UEs), that there is a "gNB BWP ID"
(as used by the gNB), which can be any BWP ID X, and one "UE BWP ID",
which is always 1. This commit implements this distinction.