Auto merge of #462 - semarie:openbsd-i686-correct, r=alexcrichton
Auto merge of #462 - semarie:openbsd-i686-correct, r=alexcrichton

i686-unknown-openbsd libc correction

Now I had been able to run testsuite on i686-unknown-openbsd, here a batch of corrections.

- `suseconds_t` is `c_long` (`i64` or `i32` depending the arch)
- struct siginfo_t padding adjustment (the pointer `si_addr` makes the pad to change depending pointer size)

I tested the PR on i686-unknown-openbsd and x86_64-unknown-openbsd.

zethra/libc,philippkeller/libc,rust-lang/libc,philippkeller/libc,cactorium/libc,rust-lang-nursery/libc,superriva/libc,mneumann/libc,rust-lang/libc,mneumann/libc,anatol/libc,anatol/libc,rust-lang/libc,cactorium/libc,superriva/libc,cactorium/libc,zethra/libc,zethra/libc,rust-lang-nursery/libc,anatol/libc,mneumann/libc,rust-lang-nursery/libc,superriva/libc,philippkeller/libc