Fix regression in SpanInfo haddocks for local modules

The regression was introduced in haskell#630 - it introduced `GhcSessionDeps` with the idea of reusing the GHC session built for typechecking for computing the SpanInfo, instead of rebuilding it from scratch.

But I forgot to actually reuse it, or maybe the change got lost during the merge.

src/Development/IDE/Core/Rules.hs

@@ -468,7 +468,7 @@ getSpanInfoRule :: Rules ()
 getSpanInfoRule =
     define $ \GetSpanInfo file -> do
         tc <- use_ TypeCheck file
-        packageState <- hscEnv <$> use_ GhcSession file
+        packageState <- hscEnv <$> use_ GhcSessionDeps file
 
 -- When possible, rely on the haddocks embedded in our interface files
 -- This creates problems on ghc-lib, see comment on 'getDocumentationTryGhc'