Fix building against GHC 9 / Lens 5

It looks like something in the GHC 9 / Lens 5 combination yields
unexpected results when using view on Lens', with GHC complaining that
it's passed a Lens' instead of a Getting (which should still be
compatible).  Commenting out the signatures of Ganeti.Network.poolLens,
Ganeti.Network.poolArrayLens and Ganeti.Utils.MultiMap.multiMapL makes
Ganeti build again, so I'd keep this ugly hack until we figure out
what's actually wrong.

Signed-off-by: Apollon Oikonomopoulos <apoikos@dmesg.gr>

src/Ganeti/Network.hs

@@ -87,11 +87,11 @@ data PoolPart = PoolInstances | PoolExt
 addressPoolIso :: Iso' AddressPool BA.BitArray
 addressPoolIso = iso apReservations AddressPool
 
-poolLens :: PoolPart -> Lens' Network (Maybe AddressPool)
+--poolLens :: PoolPart -> Lens' Network (Maybe AddressPool)
 poolLens PoolInstances = networkReservationsL
 poolLens PoolExt = networkExtReservationsL
 
-poolArrayLens :: PoolPart -> Lens' Network (Maybe BA.BitArray)
+--poolArrayLens :: PoolPart -> Lens' Network (Maybe BA.BitArray)
 poolArrayLens part = poolLens part . mapping addressPoolIso
 
 netIpv4NumHosts :: Network -> Integer

src/Ganeti/Utils/MultiMap.hs

@@ -91,7 +91,7 @@ multiMap :: (Ord k, Ord v) => M.Map k (S.Set v) -> MultiMap k v
 multiMap = MultiMap . M.filter (not . S.null)
 
 -- | A 'Lens' that allows to access a set under a given key in a multi-map.
-multiMapL :: (Ord k, Ord v) => k -> Lens' (MultiMap k v) (S.Set v)
+--multiMapL :: (Ord k, Ord v) => k -> Lens' (MultiMap k v) (S.Set v)
 multiMapL k f = fmap MultiMap
                  . at k (fmap (mfilter (not . S.null) . Just)
                          . f . fromMaybe S.empty)