component/h2o: Fix compilation

The development of this component happened in environment which had a lot
of libraries available.

component/h2o/buildout.cfg

@@ -18,8 +18,14 @@ configure-command = ${cmake:location}/bin/cmake .
 configure-options =
   -DCMAKE_INSTALL_PREFIX=@@LOCATION@@
   -DWITH_MRUBY=on
+  -DCMAKE_C_FLAGS="${:CMAKE_CFLAGS}"
+  -DCMAKE_CXX_FLAGS="${:CMAKE_CFLAGS}"
+  -DCMAKE_INSTALL_RPATH=${:CMAKE_LIBRARY_PATH}
+CMAKE_CFLAGS=-I${openssl:location}/include -I${zlib:location}/include
+CMAKE_LIBRARY_PATH=${openssl:location}/lib:${zlib:location}/lib
 environment =
   PKG_CONFIG_PATH=${openssl:location}/lib/pkgconfig ${zlib:location}/lib/pkgconfig ${ruby:location}/lib/pkgconfig ${bison:location}/lib/pkgconfig
-  LDFLAGS=-L${openssl:location}/lib -Wl,-rpath -Wl,${openssl:location}/lib -L${zlib:location}/lib -Wl,-rpath -Wl,${zlib:location}/lib -L${ruby:location}/lib -Wl,-rpath -Wl,${ruby:location}/lib -L${bison:location}/lib -Wl,-rpath -Wl,${bison:location}/lib
-  CXXFLAGS=-I${openssl:location}/include -I${zlib:location}/include -I${ruby:location}/include -I${bison:location}/include
+  CMAKE_INCLUDE_PATH=${openssl:location}/include:${zlib:location}/include
+  CMAKE_LIBRARY_PATH=${:CMAKE_LIBRARY_PATH}
+  LDFLAGS=-L${openssl:location}/lib -Wl,-rpath -Wl,${openssl:location}/lib -L${zlib:location}/lib -Wl,-rpath -Wl,${zlib:location}/lib
   PATH=${ruby:location}/bin:${bison:location}/bin:%(PATH)s