Add missing tags to GetCommandLogLevel.

Otherwise, log_statement = 'ddl' causes errors if those statement
types are used.

Michael Paquier, reviewed by Ashutosh Sharma

Discussion: http://postgr.es/m/CAB7nPqStC3HkE76Q1MnHsVd1vF1Td9zXApzYadzDMyLMRkkGrw@mail.gmail.com

Author: robertmhaas

src/backend/tcop/utility.c

@@ -2864,6 +2864,10 @@ GetCommandLogLevel(Node *parsetree)
 			lev = LOGSTMT_DDL;
 			break;
 
+		case T_AlterOperatorStmt:
+			lev = LOGSTMT_DDL;
+			break;
+
 		case T_AlterTableMoveAllStmt:
 		case T_AlterTableStmt:
 			lev = LOGSTMT_DDL;