proview-r: doxygen linking fix

component/proviewR/buildout.cfg

@@ -48,7 +48,7 @@ configure-command =
 make-binary =
   cd build && make
 environment =
-  PATH=${git:location}/bin:${cmake:location}/bin:${flex:location}/bin:${bison:location}/bin:%(PATH)s
+  PATH=${gcc:location}/bin:${git:location}/bin:${cmake:location}/bin:${flex:location}/bin:${bison:location}/bin:%(PATH)s
 
 [make-4]
 recipe = slapos.recipe.cmmi