Remove identity update of field componentsConfigs
Remove identity update of field componentsConfigs

... in LocalBuildInfo, getting rid of a TODO in the
process. Turns out that componentsConfigs won't be
a field in Cabal 2.0 any more, so this can be seen
as a preparation for it.

sdiehl/ghc,shlevy/ghc,snoyberg/ghc,snoyberg/ghc,olsner/ghc,sdiehl/ghc,mettekou/ghc,mettekou/ghc,olsner/ghc,olsner/ghc,shlevy/ghc,olsner/ghc,sdiehl/ghc,ezyang/ghc,sdiehl/ghc,mettekou/ghc,ezyang/ghc,ezyang/ghc,shlevy/ghc,ezyang/ghc,snoyberg/ghc,snoyberg/ghc,shlevy/ghc,snoyberg/ghc,snoyberg/ghc,mettekou/ghc,sdiehl/ghc,sdiehl/ghc,snoyberg/ghc,ezyang/ghc,shlevy/ghc,olsner/ghc,olsner/ghc,mettekou/ghc,mettekou/ghc,ezyang/ghc,olsner/ghc,shlevy/ghc,sdiehl/ghc,mettekou/ghc,shlevy/ghc,ezyang/ghc