icu: icu-config includes -arch flags

[ryandesign (Ryan Carsten Schmidt)]

icu-config output contains -arch flags:

$ icu-config --cflags
-pipe -Os -arch x86_64 -O2 -std=c99 -pedantic -Wshadow -Wpointer-arith -Wmissing-prototypes -Wwrite-strings   
$ icu-config --cxxflags
-pipe -Os -arch x86_64 -O2 -W -pedantic -Wpointer-arith -Wwrite-strings -Wno-long-long -std=c++11   
$ icu-config --ldflags
-arch x86_64  -lpthread -lm   -L/opt/local/lib -licui18n -licuuc -licudata  -lpthread -lm   

They must be removed; see PortfileRecipes#archflags

[ryandesign (Ryan Carsten Schmidt)]

Same with the pkg-config files.

[ryandesign (Ryan Carsten Schmidt)]

I've started working on this but in addition to -arch flags (which we can easily remove) the files contain other architecture-specific values, such as the size of a void pointer. I've opened an ​upstream issue to see if the developers of icu can help us by removing these differences from their files.

This matter was last considered in MacPorts in #23773 in which a very convoluted method was used to install the differing files with suffixes based on the arch.

[ryandesign (Ryan Carsten Schmidt)]

Removed -arch flags in r109411; I guess we can deal with the other issues later.