Link against zlib.

This CL reverts CL:24284 "Remove unnecessary linking of zlib." as
wimax_manager now needs to link against gdmwimax-private, which depends
on zlib.

BUG=chrome-os-partner:22784
TEST=Tested the following:
1. `FEATURES=test USE=internal emerge-lumpy wimax_manager`
2. Run network_WiMaxSmoke test.

Change-Id: I54b6be5870af444a8a497a00d2db41e6cd1fe4c3
Reviewed-on: https://chromium-review.googlesource.com/169964
Reviewed-by: Mike Frysinger <vapier@chromium.org>
Tested-by: Ben Chan <benchan@chromium.org>
Commit-Queue: Ben Chan <benchan@chromium.org>
1 file changed