glsl/build: build builtin_compiler with VISIBILITY_CFLAGS

libglslcore.la and libglcpp.la that are built with builtin_compiler are also
linked to by drivers not using libdricore.  Since there is no public symbol in
them, it is better to mark all symbols hidden.

Signed-off-by: Chia-I Wu <olvaffe@gmail.com>
Reviewed-by: Matt Turner <mattst88@gmail.com>

src/glsl/builtin_compiler/Makefile.am

@@ -26,7 +26,8 @@ AM_CFLAGS = \
 	-I $(top_srcdir)/src/mesa \
 	-I $(GLSL_SRCDIR) \
 	-I $(GLSL_SRCDIR)/glcpp \
-	-I $(GLSL_BUILDDIR)
+	-I $(GLSL_BUILDDIR) \
+	$(VISIBILITY_CFLAGS)
 
 if CROSS_COMPILING
 proxyCC = @CC_FOR_BUILD@