fix typo causing compilation failure on SPARC (ArchSparc -> ArchSPARC)
fix typo causing compilation failure on SPARC (ArchSparc -> ArchSPARC)

(cherry picked from commit 00c8076ecf441e6be5cacafc78a98f7ab38ddad4)

GaloisInc/halvm-ghc,GaloisInc/halvm-ghc,GaloisInc/halvm-ghc,GaloisInc/halvm-ghc,GaloisInc/halvm-ghc,GaloisInc/halvm-ghc,GaloisInc/halvm-ghc