go.blog: use the right declaration for Go's main function

OMG department.
Thanks to an anonymous correspondent for pointing it out.
Why did no one notice this?

The original translation here is lexically similar but very wrong.
I had C on the brain when I wrote it. That doesn't happen so much
any more.

LGTM=robert.hencke
R=golang-codereviews, robert.hencke
CC=golang-codereviews
https://golang.org/cl/99160043
1 file changed