handle external zlib headers
Since the zlib headers aren't exported/installed, we need to symlink
them in here for the compiler to find.
BUG=23171578
Change-Id: I5a2ef5d1508966902c6a722593c412a055917973
diff --git a/external-packages/include/zconf.h b/external-packages/include/zconf.h
new file mode 120000
index 0000000..b6ce3f9
--- /dev/null
+++ b/external-packages/include/zconf.h
@@ -0,0 +1 @@
+../../../../zlib/zconf.h
\ No newline at end of file
diff --git a/external-packages/include/zlib.h b/external-packages/include/zlib.h
new file mode 120000
index 0000000..d989de9
--- /dev/null
+++ b/external-packages/include/zlib.h
@@ -0,0 +1 @@
+../../../../zlib/zlib.h
\ No newline at end of file
