lcms2: add upstream security fix for CVE-2018-16435

lcms2: add upstream security fix for CVE-2018-16435

Little CMS (aka Little Color Management System) 2.9 has an integer overflow
in the AllocateDataSet function in cmscgats.c, leading to a heap-based
buffer overflow in the SetData function via a crafted file in the second
argument to cmsIT8LoadFromFile.

For more details, see:
https://github.com/mm2/Little-CMS/issues/171
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-16435

The upstream fix unfortunately includes a number of unrelated changes, but
thse files are not used when building for Linux.

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>