V8 zlib target fails for cross-compilation

[targos]

https://ci.nodejs.org/job/node-cross-compile/27290/nodes=cross-compiler-armv7-gcc-6/console

13:42:45 gyp: Dependency '/home/iojs/build/workspace/node-cross-compile/tools/v8_gypfiles/v8.gyp:v8_zlib#host' not found while trying to load target /home/iojs/build/workspace/node-cross-compile/tools/v8_gypfiles/v8.gyp:v8_base_without_compiler#host

[targos]

this is fixed