Fixed Makefile for libpng

Fedora patch says:
-beos_ARCH_LINKS:="-lintl $(PNG) -lz -lbe -liconv $(FRIBIDI_LIB)"
+beos_ARCH_LINKS:=-lintl $(PNG) -lbe -liconv $(FRIBIDI_LIB) $(COMMON_LIB)

But the deleted line is not similar to the one in this Makefile