GRASS compilation fix 2

Author: blazek

src/providers/grass/CMakeLists.txt

@@ -80,6 +80,7 @@ SET ( FUNCTIONS
   "G_init_range"
   "G_is_c_null_value"
   "G_is_d_null_value"
+  "G_is_f_null_value"
   "G__malloc"
   "G_percent"
   "G_program_name"

src/providers/grass/qgsgrassgislib.cpp

@@ -294,6 +294,7 @@ int G_done_msg( const char *msg, ... )
 
 char * QgsGrassGisLib::G_find_cell2( const char * name, const char * mapset )
 {
+  Q_UNUSED( name );
   Q_UNUSED( mapset );
   QgsDebugMsg( "name = " + QString( name ) );
   QString ms = "qgis";