Const correctness for rasterblock

Author: elpaso

python/core/auto_generated/raster/qgsrasterblock.sip.in

@@ -186,7 +186,7 @@ Read a single value
 :return: color *
 %End
 
-    bool isNoData( int row, int column );
+    bool isNoData( int row, int column ) const;
 %Docstring
 Check if value at position is no data
 
@@ -196,7 +196,7 @@ Check if value at position is no data
 :return: true if value is no data *
 %End
 
-    bool isNoData( qgssize row, qgssize column );
+    bool isNoData( qgssize row, qgssize column ) const;
 %Docstring
 Check if value at position is no data
 
@@ -206,7 +206,7 @@ Check if value at position is no data
 :return: true if value is no data *
 %End
 
-    bool isNoData( qgssize index );
+    bool isNoData( qgssize index ) const;
 %Docstring
 Check if value at position is no data