Remove unreachable code. Fix a shift UB problem introduced yesterday

and discovered by OSSFuzz.

FossilOrigin-Name: 078dbff04a95a001bbd8690ab08038fbb5506899df8290991b53fd1122a4c30c

src/sqliteInt.h

@@ -2762,7 +2762,7 @@ struct Expr {
 #define EP_ConstFunc  0x080000 /* A SQLITE_FUNC_CONSTANT or _SLOCHNG function */
 #define EP_CanBeNull  0x100000 /* Can be null despite NOT NULL constraint */
 #define EP_Subquery   0x200000 /* Tree contains a TK_SELECT operator */
-#define EP_Alias      0x400000 /* Is an alias for a result set column */
+                 /*   0x400000 // Available */
 #define EP_Leaf       0x800000 /* Expr.pLeft, .pRight, .u.pSelect all NULL */
 #define EP_WinFunc   0x1000000 /* TK_FUNCTION with Expr.y.pWin set */
 #define EP_Subrtn    0x2000000 /* Uses Expr.y.sub. TK_IN, _SELECT, or _EXISTS */