This libgo patch declares the return type of the C getaddrinfo
function, when called from Go, as int32 rather than int.  That is
important because getaddrinfo returns negative numbers on error, and
so numbers like -2 in int32 were being treated as 0xfffffffe in int,
which in Go is a 64 bit type.  This caused comparisons against
EAI_NONAME, etc., to fail.  This fixes https://golang.org/issue/23645.
Bootstrapped and ran Go testsuite on x86_64-pc-linux-gnu.  Committed
to mainline.

Ian