icon for linux (merge from devbr6)

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@37855 15284696-431f-4ddb-bdfa-cd5b030d7da7

gui/icons/Makefile

@@ -2,7 +2,7 @@ MODULE_TOPDIR = ../..
 
 include $(MODULE_TOPDIR)/include/Make/Dir.make
 
-SRCICO := $(wildcard *.ico)
+SRCICO := $(wildcard *.ico *.png)
 SRCICONS := $(wildcard grass/*.gif grass/vdigit/*.gif grass/vdigit/*.xbm silk/*.png grass2/*.png)
 ETCICONS := $(patsubst %,$(ETC)/gui/icons/%,$(SRCICONS) $(SRCICO))
 HTMLICONS := $(patsubst %,$(HTMLDIR)/icons/%,$(SRCICONS))