[GRASS] support extension filter in file output, fixes #5011

Author: blazek

src/plugins/grass/modules/r.out.vtk.qgm

@@ -12,5 +12,5 @@
 	<option key="z" version_min="7.0"/>
 	<option key="zscale" version_min="7.0"/>
 	<option key="precision" version_min="7.0"/>
-	<file key="output" type="new" filters="VTK (*.vtk)" />
+	<file key="output" type="new" filters="VTK (*.vtk *.VTK);;All files(*.*)" />
 </qgisgrassmodule>

src/plugins/grass/modules/v.out.vtk.qgm

@@ -5,5 +5,5 @@
 	<option key="input" layeroption="layer" typeoption="type" />
 	<option key="scale" version_max="6.4"/>
 	<option key="zscale" version_min="7.0"/>
-	<file key="output" filters="VTK (*.vtk)"/>
+	<file key="output" type="new" filters="VTK (*.vtk *.VTK);;All files(*.*)"/>
 </qgisgrassmodule>

src/plugins/grass/qgsgrassmoduleparam.cpp

@@ -1581,7 +1581,7 @@ void QgsGrassModuleFile::browse()
       selectedFile = lastDir;
 
     if ( mType == New )
-      selectedFile = QFileDialog::getSaveFileName( this, 0, selectedFile );
+      selectedFile = QFileDialog::getSaveFileName( this, 0, selectedFile, mFilters );
     else if ( mType == Directory )
       selectedFile = QFileDialog::getExistingDirectory( this, 0, selectedFile );
     else