updates source for ICON grid file

mesh/Makefile

@@ -6,13 +6,10 @@ ELMER_MESH_FILE_LINK = \
 	https://kannu.csc.fi/s/npxnWEzPowrd2by/download/MESH_Greenland.tgz
 ELMER_MESH_FILE = $(notdir $(ELMER_MESH_FILE_LINK))
 
-# for some reason this link currently does not work, you will have to get the
-# file directly from Levante
-# (levante.dkrz.de:/pool/data/ICON/grids/public/mpim/0054/icon_grid_0054_R02B08_G.nc)
-# or somewhere else
-ICON_GRID_FILE_LINK = \
-	http://icon-downloads.mpimet.mpg.de/grids/public/mpim/0054/icon_grid_0054_R02B08_G.nc
-ICON_GRID_FILE = $(notdir $(ICON_GRID_FILE_LINK))
+# on LUMI the ICON grid file should be available at:
+#   /appl/local/climatedt//pool/data/ICON/grids/public/mpim/0054
+ICON_GRID_FILE_PATH ?= /pool/data/ICON/grids/public/mpim/0054
+ICON_GRID_FILE = icon_grid_0054_R02B08_G.nc
 
 .PHONY: all clean
 
@@ -28,5 +25,4 @@ $(ELMER_MESH_FILE):
 	tar xvf $@
 
 $(ICON_GRID_FILE):
-	echo fetching: $@
-	curl -sL $(ICON_GRID_FILE_LINK) -o $@
+	[ -f $(ICON_GRID_FILE_PATH)/$@ ] && ln -s $(ICON_GRID_FILE_PATH)/$@ || exit 1