Fix mixup of bool and ternary value

Not currently a problem, but could be with stricter bool behavior under
stdbool or C++.

Reviewed-by: Andres Freund <andres@anarazel.de>

src/include/access/gin_private.h

@@ -281,7 +281,7 @@ typedef struct GinScanKeyData
 	int			nadditional;
 
 	/* array of check flags, reported to consistentFn */
-	bool	   *entryRes;
+	GinTernaryValue *entryRes;
 	bool		(*boolConsistentFn) (GinScanKey key);
 	GinTernaryValue (*triConsistentFn) (GinScanKey key);
 	FmgrInfo   *consistentFmgrInfo;