Revert "deps: fix gypi sysroot settings on V8"
This reverts commit fc45b16e.
This commit was a fix for failures happening in node-test-commit-v8-linux
in v8.x-staging
because of upstream changes, but apparently, the problem was fixed upstream and now this commit is invalid. Since node-test-commit-v8-linux
I suggest we revert this commit to avoid future issues.