Coverity: Variable unused

Remove unused varaible.
For tuplesort.h, we doesn't support mksort based cluster,
so we should just set is_mk_tuplesortstate to false

src/backend/access/external/external.c

@@ -773,7 +773,6 @@ create_external_scan_uri_list(ExtTableEntry *ext, bool *ismasteronly)
 
 				uri = ParseExternalTableUri(uri_str);
 
-				found_candidate = false;
 				found_match = false;
 
 				/*
@@ -804,9 +803,6 @@ create_external_scan_uri_list(ExtTableEntry *ext, bool *ismasteronly)
 								continue;	/* skip it */
 						}
 
-						/* a valid primary segdb exist on this host */
-						found_candidate = true;
-
 						if (segdb_file_map[segind] == NULL)
 						{
 							/* segdb not taken yet. assign this URI to this segdb */

src/backend/commands/exttablecmds.c

@@ -88,7 +88,6 @@ DefineExternalRelation(CreateExternalStmt *createExtStmt)
 	char	   *locationUris = NULL;
 	char	   *locationExec = NULL;
 	char	   *commandString = NULL;
-	char	   *customProtName = NULL;
 	char		rejectlimittype = '\0';
 	char		formattype;
 	int			rejectlimit = -1;
@@ -329,9 +328,6 @@ DefineExternalRelation(CreateExternalStmt *createExtStmt)
 									GetAssignedOidsForDispatch(),
 									NULL);
 	}
-
-	if (customProtName)
-		pfree(customProtName);
 }
 
 /*

src/include/utils/tuplesort.h

@@ -288,7 +288,6 @@ switcheroo_tuplesort_begin_cluster(TupleDesc tupDesc,
 			tuplesort_begin_cluster_pg(tupDesc, indexRel,
 									   workMem, randomAccess);
 	}
-	state->is_mk_tuplesortstate = gp_enable_mk_sort;
 	state->is_mk_tuplesortstate = false;
 	return state;
 }