use shared libft2 with new libpng/zlib deps

FreeType now depends upon libpng and zlib. While I'm adding those
dependencies, I might as well also switch libft2 to a shared
library...

Bug: 9603326
Change-Id: Idfd56892fe627ff22521b12e4dbb199d27161746
diff --git a/Android.mk b/Android.mk
index bef48c0..6e4917d 100644
--- a/Android.mk
+++ b/Android.mk
@@ -149,8 +149,7 @@
 
 LOCAL_SHARED_LIBRARIES += liblog libcutils libutils libEGL libGLESv1_CM libGLESv2 libbcc
 LOCAL_SHARED_LIBRARIES += libui libbcinfo libLLVM libgui libsync libdl
-
-LOCAL_STATIC_LIBRARIES := libft2
+LOCAL_SHARED_LIBRARIES += libft2 libpng libz
 
 LOCAL_C_INCLUDES += external/freetype/include
 LOCAL_C_INCLUDES += frameworks/compile/libbcc/include