hg: jdk/sandbox: 8204967: Resolve disabled warnings for libunpack

[chris.hegarty at oracle.com]

Changeset: 11b3e9c1aa5e
Author:    sdama
Date:      2018-06-28 19:44 +0530
URL:       http://hg.openjdk.java.net/jdk/sandbox/rev/11b3e9c1aa5e

8204967: Resolve disabled warnings for libunpack
Summary: Fixed warnings for libunpack
Reviewed-by: jlaskey

! make/launcher/Launcher-jdk.pack.gmk
! src/jdk.pack/share/native/common-unpack/unpack.cpp
! src/jdk.pack/share/native/common-unpack/zip.cpp