Fix linking with libGL

src/project.conf

@@ -1,11 +1,12 @@
 targets=libGToolkit
 cppflags_force=-I ../include
-cflags_force=-W `pkg-config --cflags gl`
+cflags_force=-W
 cflags=-Wall -fPIC -g -O2 -pedantic
 dist=Makefile,common.h,gwidget.h
 
 [libGToolkit]
 type=library
+cflags=`pkg-config --cflags gl`
 ldflags=`pkg-config --libs gl`
 install=$(PREFIX)/lib
 sources=common.c,gwindow.c,gtoolkit.c

tools/project.conf

@@ -1,7 +1,8 @@
 targets=test
 cppflags_force=-I ../include
-cflags_force=-W
+cflags_force=-W `pkg-config --cflags gl`
 cflags=-Wall -fPIC -g -O2 -pedantic
+ldflags_force=`pkg-config --libs gl`
 dist=Makefile
 
 [test]