Add support for MacOS universal dylib for lzss library

[manchoz]

Add support for MacOS universal dylib for lzss library.

A new version of lzss.dylib has been generated in Universal (aka. fat) format: it now supports both x64 (Intel) and arm64 (Apple Silicon) Macs.

OBSOLETED. SEE BELOW

Steps to generate it:

$ clang lzss.c -o lzss.dylib -dynamiclib -std=gnu99 -fvisibility=hidden -fvisibility-inlines-hidden -arch arm64 -arch    x86_64 
$ strip -x lzss.dylib

Lipo Info

$ lipo -detailed_info lzss.dylib
Fat header in: lzss.dylib
fat_magic 0xcafebabe
nfat_arch 2
architecture x86_64
    cputype CPU_TYPE_X86_64
    cpusubtype CPU_SUBTYPE_X86_64_ALL
    capabilities 0x0
    offset 16384
    size 49560
    align 2^14 (16384)
architecture arm64
    cputype CPU_TYPE_ARM64
    cpusubtype CPU_SUBTYPE_ARM64_ALL
    capabilities 0x0
    offset 81920
    size 50104
    align 2^14 (16384)

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[manchoz]

Actual steps to generate it:

mv lzss.dylib lzss.dylib.x86_64
clang -std=c11 -Wall -Wextra -pedantic -c -fPIC lzss.c -o lzss.o
clang -shared lzss.o -o lzss.dylib.arm64
lipo -create lzss.dylib.x86_64 lzss.dylib.arm64 -o lzss.dylib

In the case of changes to lzss.c, we must compile the .o files for x86_64 and amd64 independently and then regenerate the .o and the .dylib from them.