Fix a reoccuring typo in load-combine tests

   %tmp = bitcast i32* %arg to i8*
   %tmp1 = getelementptr inbounds i8, i8* %tmp, i32 0
-  %tmp2 = load i8, i8* %tmp, align 1
+  %tmp2 = load i8, i8* %tmp1, align 1

This doesn't change the semantics of the tests but makes use of %tmp1 which was originally intended.

llvm-svn: 328642