Increment DFAStateEntryTable index for sentinel entry.

Increment DFAStateEntryTable index for sentinel entry.

When adding the {-1, -1} entry to the DFAStateInputTable, we
need to increment the index used to populate the DFAStateEntryTable.
Otherwise, the entry table will be off by one for each transition
after the {-1, -1} entry. PR11908.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149713 91177308-0d34-0410-b5e6-96231b3b80d8