db_unixodbc: data converting log improvement - errors should be logged as such

src/modules/db_unixodbc/val.c

@@ -151,7 +151,7 @@ int db_unixodbc_val2str(const db1_con_t* _c, const db_val_t* _v, char* _s, int*
 			break;
 
 		default:
-			LM_DBG("unknown data type\n");
+			LM_ERR("unknown data type\n");
 			return -10;
 	}
 }