Clean up libzipfile Android.mk

Switch to using libz instead of libunz as per the note in
external/zlib/Android.mk.

Removed LOCAL_C_INCLUDES which are no longer necessary as zlib
now uses the LOCAL_EXPORT_C_INCLUDE_DIRS mechanism.

Tested compiling the projects that make use of libzipfile using
a clean out dir with both aosp_flounder-userdebug and aosp_arm-eng

make -j16 test_zipfile fastboot adb adbd libSR_Core libsrec_jni

Change-Id: I5fdf34b6c272ae64c406e5b77ab67a5f5e4b5890
diff --git a/libzipfile/Android.mk b/libzipfile/Android.mk
index 12a2229..f054e15 100644
--- a/libzipfile/Android.mk
+++ b/libzipfile/Android.mk
@@ -7,13 +7,10 @@
 	centraldir.c \
 	zipfile.c
 
-LOCAL_STATIC_LIBRARIES := \
-	libunz
+LOCAL_STATIC_LIBRARIES := libz
 
 LOCAL_MODULE:= libzipfile
 
-LOCAL_C_INCLUDES += external/zlib
-
 LOCAL_CFLAGS := -Werror
 
 LOCAL_MULTILIB := both
@@ -27,13 +24,10 @@
 	centraldir.c \
 	zipfile.c
 
-LOCAL_STATIC_LIBRARIES := \
-	libunz
+LOCAL_STATIC_LIBRARIES := libz
 
 LOCAL_MODULE:= libzipfile
 
-LOCAL_C_INCLUDES += external/zlib
-
 LOCAL_CFLAGS := -Werror
 
 include $(BUILD_STATIC_LIBRARY)
@@ -45,12 +39,10 @@
 LOCAL_SRC_FILES:= \
 	test_zipfile.c
 
-LOCAL_STATIC_LIBRARIES := libzipfile libunz
+LOCAL_STATIC_LIBRARIES := libzipfile libz
 
 LOCAL_MODULE := test_zipfile
 
-LOCAL_C_INCLUDES += external/zlib
-
 LOCAL_CFLAGS := -Werror
 
 include $(BUILD_HOST_EXECUTABLE)