Revert "rts/sm/Storage.c: tweak __clear_cache proto for clang"
Revert "rts/sm/Storage.c: tweak __clear_cache proto for clang"

This reverts commit 9492703a5862ee8623455209e50344cf8c4de077.

Incomplete patch (missing begin, end assignments).

sdiehl/ghc,shlevy/ghc,sdiehl/ghc,ezyang/ghc,ezyang/ghc,sdiehl/ghc,sdiehl/ghc,shlevy/ghc,sdiehl/ghc,shlevy/ghc,ezyang/ghc,ezyang/ghc,ezyang/ghc,sdiehl/ghc,sdiehl/ghc,shlevy/ghc,shlevy/ghc,shlevy/ghc,ezyang/ghc,shlevy/ghc,ezyang/ghc