Add IFLA_INFO_ consts

See https://github.com/torvalds/linux/blob/54ecb8f7/include/uapi/linux/if_link.h#L354-L362

Support vxWorks in libc-test

r? @gnzlbg

Use minimal profile for rustup

Haven't tested it but should fix issue from https://github.com/rust-lang/libc/pull/1549#issuecomment-542203074

Haiku: Fix constants for S_IFIFO and S_IFCHR

Some updates for vxWorks

adding FIOGETNAME which is used by ioctl() to get file path
adding PATH_MAX
use type c_int for _PARM_NAME_MAX and _PARM_PATH_MAX

adding PATH_MAX

use type c_int for _PARM_NAME_MAX and _PARM_PATH_MAX

See
https://github.com/torvalds/linux/blob/54ecb8f7/include/uapi/linux/if_link.h#L354-L362

sync with rust-lang/libc master

Add `pthread_main_np` to FreeBSD-like and `_lwp_self` to NetBSD

Sync to rust-lang/libc master

update rtpSpawn prototype

Fix max_align_t

Sync to rust-lang/libc branch master

VxWorks libc cleanups and fixes for some libc-test issues

move rtpSpawn and RTP_ID_ERROR from libstd to libc

use union for unions

Add environment variable FILTER to choose which target(s) to run

Sync to rust-lang/libc master

Skip max_align_t in FreeBSD10

This error was able to land because FreeBSD10 is not checked by bors yet (see: RCS PR: https://github.com/rust-lang/rust-central-station/pull/481) .

Fixes

Two patches fixing minor issues.