update to icu has again broken all the macports-clang compilers

[Joshua Root]

On 2020-8-13 00:37 , Ken Cunningham wrote:
> not exactly sure how I'm going to get around this just yet
> 
> have to find some compiler that still works somewhere -- gcc? to rebuild libxmls2 and then again rebuild libxml2 +universal once some clang works again...
> 
> configure:3623: $? = 1
> configure:3643: checking whether the C compiler works
> configure:3665: /opt/local/bin/clang-mp-3.7 -pipe -Os -arch x86_64 -arch i386 -I/opt/local/include -L/opt/local/lib -Wl,-headerpad_max_install_names -arch x86_64 -arch i386 conftest.c  >&5
> dyld: Library not loaded: /opt/local/lib/libicui18n.65.dylib
>   Referenced from: /opt/local/lib/libxml2.2.dylib
>   Reason: image not found
> 

I notice clang-3.7 doesn't actually depend on libxml2, unlike later
clangs. Probably for precisely this reason? But that means whatever it's
doing to avoid using libxml2 isn't working.

- Josh