Add append2simg.

Append2simg is a small utility designed to glue data to the end
of a sparse image. Beware that it doesn't do anything clever with
that data.

Change-Id: I33af330cb4f77e0842375797a35aebbb6af60163
diff --git a/libsparse/Android.mk b/libsparse/Android.mk
index 9025cc0..a21e090 100644
--- a/libsparse/Android.mk
+++ b/libsparse/Android.mk
@@ -82,8 +82,8 @@
 
 
 include $(CLEAR_VARS)
-LOCAL_SRC_FILES := simg2simg.c
-LOCAL_MODULE := simg2simg
+LOCAL_SRC_FILES := append2simg.c
+LOCAL_MODULE := append2simg
 LOCAL_STATIC_LIBRARIES := \
     libsparse_host \
     libz