Fix building against Lens 5 by commenting out type signatures(!).

Taken from upstream:

  https://github.com/ganeti/ganeti/commit/5e30bad1bba63c9f6c782003ef2560f107a0ba24

diff --git a/src/Ganeti/Network.hs b/src/Ganeti/Network.hs
index 1cb6aa1ec..696c1cd1b 100644
--- a/src/Ganeti/Network.hs
+++ b/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
diff --git a/src/Ganeti/Utils/MultiMap.hs b/src/Ganeti/Utils/MultiMap.hs
index d54da3ab0..279e9335a 100644
--- a/src/Ganeti/Utils/MultiMap.hs
+++ b/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)
-- 
2.41.0

/installer/steps.scm'>
<input type='hidden' name='id' value='f0752de257d5521f7cbe31a4c0f5114694747a08'/><select name='qt'>
<option value='grep'>log msg</option>
<option value='author'>author</option>
<option value='committer'>committer</option>
<option value='range'>range</option>
</select>
<input class='txt' type='search' size='10' name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/guix/log/?id=f0752de257d5521f7cbe31a4c0f5114694747a08'>root</a>/<a href='/guix/log/gnu?id=f0752de257d5521f7cbe31a4c0f5114694747a08'>gnu</a>/<a href='/guix/log/gnu/installer?id=f0752de257d5521f7cbe31a4c0f5114694747a08'>installer</a>/<a href='/guix/log/gnu/installer/steps.scm?id=f0752de257d5521f7cbe31a4c0f5114694747a08'>steps.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/gnu/installer/steps.scm?id=f0752de257d5521f7cbe31a4c0f5114694747a08&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2022-11-02 15:52:19 +0100'>2022-11-02</span></td><td><a href='/guix/commit/gnu/installer/steps.scm?id=62a3756bd90c922c701e899a6c01c556d8e3c75a'>installer: Skip the backtrace page on user abort.</a><span class='msg-avail'>...<span class='msg-tooltip'>When the user aborts the installation because a core dump is discovered or the
installation command failed, displaying the abort backtrace doesn't make much
sense. Hide it when the abort condition is &amp;user-abort-error and skip directly
to the dump page.

* gnu/installer/steps.scm (&amp;user-abort-error): New variable.
(user-abort-error?): New procedure.
* gnu/installer/newt/final.scm (run-install-failed-page): Raise a
user-abort-error.
* gnu/installer/newt/welcome.scm (run-welcome-page): Ditto.
* gnu/installer.scm (installer-program): Hide the backtrace page and directly
propose to dump the report when the a &amp;user-abort-error is raised.
</span></span></td><td>Mathieu Othacehe</td></tr>
<tr><td><span title='2022-08-08 11:54:25 +0200'>2022-08-08</span></td><td><a href='/guix/commit/gnu/installer/steps.scm?id=ff9522fb69b9f4a31a5b766029e26dc53a2d1cf8'>installer: Add comments and vertical space to the generated config.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/installer/parted.scm (user-partitions-&gt;configuration): Introduce
vertical space and a comment.
* gnu/installer/services.scm (G_): New macro.
(%system-services): Add comment for OpenSSH.
(system-services-&gt;configuration): Add vertical space and comments.
* gnu/installer/user.scm (users-&gt;configuration): Add comment.
* gnu/installer/steps.scm (format-configuration): Add comment.
(configuration-&gt;file): Expound leading comment.  Pass #:format-comment
to 'pretty-print-with-comments/splice'.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2022-08-08 11:54:24 +0200'>2022-08-08</span></td><td><a href='/guix/commit/gnu/installer/steps.scm?id=cd1a98b928be9602ebf103744164ace7bfcae22c'>installer: Render the final configuration with (guix read-print).</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/installer.scm (module-to-import?): Return #t for (guix read-print).
* gnu/installer/steps.scm (configuration-&gt;file): Use
'pretty-print-with-comments/splice' instead of 'for-each' and 'pretty-print'.
</span></span></td><td>Ludovic Courtès</td></tr>