Allow an index to be used for sorting even if prior terms of the index

are constrained by IN operators.

FossilOrigin-Name: 2cef8b68f0e1216cf68bb7dd45a5a9a330748070

src/sqliteInt.h

@@ -1965,6 +1965,7 @@ struct WhereLevel {
       struct InLoop {
         int iCur;              /* The VDBE cursor used by this IN operator */
         int addrInTop;         /* Top of the IN loop */
+        u8 eEndLoopOp;         /* IN Loop terminator. OP_Next or OP_Prev */
       } *aInLoop;           /* Information about each nested IN operator */
     } in;                 /* Used when plan.wsFlags&WHERE_IN_ABLE */
     Index *pCovidx;       /* Possible covering index for WHERE_MULTI_OR */