[WebAssembly] Rename a variable in CFGSort (NFC)

Class `RegionInfo` was `SortUnitInfo` before, so the variables were
named `SUI`. Now the class name is `RegionInfo`, so this renames `SUI`
to `RI`, matching the class name.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@356861 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed