logging: use a different color tone for DLOOP
logging: use a different color tone for DLOOP

Normal blue (34) is really hard to read on terminals with dark
background.  Let's use light blue (94) instead.

Change-Id: Iadc9b8fb74ec17455435893a532c2f12e02cb804

osmocom/osmo-bts,osmocom/osmo-bts,osmocom/osmo-bts