[icu] Add option to disable dyload

[jgsogo]

Specify library name and version: icu/*

On my quest to compile boost with ICU I've found it is not working in Linux because the test during config for ICU fails to link due to dl-xxx symbols. It looks like it is an old friend here bincrafters/community#647

Adding this option to ICU and using it to compile boost+icu I can finally find ICU libraries \o/

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[conan-center-bot]

All green in build 1 (85b762661ca1f2879a0961538ded83e416e617d2)! 😊

• icu/64.2: Generated 130 packages. All logs here