www/h2o: update 2.0.0 -> 2.0.1

This is a bug-fix release of 2.0 series, fixing following issues found in 2.0.0.

• [fastcgi] fix internal server error when PHP returns a huge header #958
• [http2] recognize link header containing multiple links #950
• [libh2o] fix resource leaks upon startup failure #936
• [libh2o] do not require linking to libbrotli externally #941

Changes: https://github.com/h2o/h2o/releases/tag/v2.0.1

PR: 210769
Submitted by: Dave Cottlehuber <dch@skunkwerks.at> (maintainer)