Enable evaluation of primary key if table name is given in the format…

… schema.tablename

SQL server plugin allows to omit "USING UNIQUE" by automatically
retrieving the name of the table's primary key. This did only work if
the table was just mentioned through it name. The fix allows you to
specify the table name as
[SERVERNAME].[DATABASENAME].[SCHEMANAME].[TABLENAME]

mapmssql2008.c

@@ -2105,7 +2105,7 @@ int msMSSQL2008LayerRetrievePK(layerObj *layer, char **urid_name, char* table_na
            "                     sys.tables ON sys.indexes.object_id = sys.tables.object_id INNER JOIN "
            "                     sys.index_columns ON sys.indexes.object_id = sys.index_columns.object_id AND sys.indexes.index_id = sys.index_columns.index_id ON "
            "                     sys.columns.object_id = sys.index_columns.object_id AND sys.columns.column_id = sys.index_columns.column_id "
-           "WHERE     (sys.indexes.is_primary_key = 1) AND (sys.tables.name = N'%s') ",
+           "WHERE     (sys.indexes.is_primary_key = 1) AND (sys.tables.name = PARSENAME(N'%s',1)) ",
            table_name);
 
   if (debug) {