graphics/mupdf: fix build with big-endian architectures

Remove files/patch-thirdparty_lcms2_src_cmsmd5.c to fix build.

The port builds without this patch now and the patch actually breaks build.

PR: 237930
Approved by: linimon (mentor), uzsolt@uzsolt.hu (maintainer)
Differential Revision: https://reviews.freebsd.org/D20400