- Copy 17 functions definitions from src/unix/mod.rs
      to src/unix/bsd/mod.rs src/unix/haiku/mod.rs
      src/unix/notbsd/linux/mod.rs and src/unix/solaris/mod.rs
    - Add some functions to android that was cfged out
    - Remove cf* and tc* functions implementations for android
      (they are available with api >= 12, which was release in 2011)

- some tests are failing
- remove readlink, timegm and sig* functions in favor of the
  unix/mod.rs definitions
- remove time64_t (it is not defined for aarch64)
- move some definitions to android/b32.rs and create appropriated
  definitions in android/b64.rs

Having the B* constants in `unix/notbsd/mod.rs` passed CI tests
except for powerpc.  So we'll try moving into individual
arch/ABI that the CI tests cover for now. This commit should
pass for the following:

- mips32
- mips64
- musl32
- musl64
- android32
- android64
- arm32
- aarch64
- x86
- x86_64

Then we can figure out the powerpc variants.  This also prevents
potential errors for sparc64 which is not covered by CI.

This is useful to decide if value returned from getaddrinfo is actual
error or you should look at errno instead.

Add netlink constants from linux/netlink.h

Signed-off-by: Jana Radhakrishnan <mrjana@gmail.com>

I duplicated the code for android, because the member of cpu_set_t
is private, thus cannot be accessed in the parent mod. I would have
had to configure the name anyway based on the platform, because it
differs between the platforms.

Following types and function have been added:
* pthread_cond_init
* pthread_condattr_t
* pthread_condattr_init
* pthread_condattr_destroy
* pthread_condattr_setclock [0]
* pthread_condattr_getclock [0][1]

[0] Not available on OSX.
[1] May be unavailable on NetBSD, it is a very recent addition.
    Left out from openbsdlike hierarchy for now.

Copy them into individual platform files instead. Fixes musl build.

linux: /usr/include/bits/confname.h (taken from redhat, checked against https://github.com/cpc26/abi_linux/blob/master/linux-abi/branches/IBCS3/cxenix/pathconf.c)
android: https://android.googlesource.com/platform/development/+/android-4.3_r1.1/ndk/platforms/android-3/include/pathconf.h
mac: taken from /usr/include/sys/unistd.h

Sadly, the sysinfo struct varies slightly between Musl and Glibc / Bionic.

This means that users need to be careful when using the uptime, and should
always cast it to a signed value. Why uptime can be signed is beyond me...

Adding program_invocation_short_name for Linux (Musl and glibc).

Adding __progname for Android. This is a little different, but
is a safer alternative to using argv[0], which may not exist, and
includes Android's default application name (currently '<unknown>').

Adding these functions and externs means it is possible for all
but Windows applications to safely discover their
name, rather than rely on argv[0] parsing, /proc/self/exe, etc.

A bunch of definitions were duplicated across, eg, android and linux.
This commit pulls these up to higher levels where they can be shared.

There are many constants defined by langinfo, but we have the
new types, locale_t and nl_item.

We also have several functions, not all of which exist for every
platform:

nl_langinfo
nl_langinfo_l
newlocale
duplocale
freelocale
uselocale
querylocale

Linux-likes have more locale categories than the BSDs (except for
musl). We define the common set of categories at the
src/unix/notbsd/mod.rs level, and leave the rest to the
platform-specific modules.

This commit changes most uses of cfg_if as follows:
- fallthrough `else` usage is avoided for architecture or OS specific
  items
- a comment is added in the final `else` clause to signal intent someone
  modifying

It is safer to omit items than include ones for the wrong platform or
architecture.