Fix the SYSCALLS.TXT documentation and remove a dead script.

We use the system call constants from the kernel header files now,
so there's no need to check that they've been correctly transcribed
into SYSCALLS.TXT.

This is a work in progress. I've added TODOs to SYSCALLS.TXT explaining
what's left to do.

Change-Id: I3b86acfe7f84b4da1c802ee5a4ef13a2e83e7939
Merge "Fix the SYSCALLS.TXT documentation and remove a dead script."
Prevent name conflict for eventfd.cpp and eventfd.s when building libc.a

 - eventfd.cpp and eventfd.s will output to the same file when building libc.a
   out/target/product/*/obj/STATIC_LIBRARIES/libc_intermediates/WHOLE/libc_common_objs/eventfd.o
 - And then `eventfd` will undefined when statically linked to libc.

Also add a unit test.

Change-Id: Ib310ade3256712ca617a90539e8eb07459c98505
Merge "Prevent name conflict for eventfd.cpp and eventfd.s when building libc.a"
Make abort messages available to debuggerd.

This adds __libc_fatal, cleans up the internal logging code a bit more,
and switches suitable callers over to __libc_fatal. In addition to logging,
__libc_fatal stashes the message somewhere that the debuggerd signal handler
can find it before calling abort.

In the debuggerd signal handler, we pass this address to debuggerd so that
it can come back with ptrace to read the message and present it to the user.

Bug: 8531731
Change-Id: I416ec1da38a8a1b0d0a582ccd7c8aaa681ed4a29
Merge "Make abort messages available to debuggerd."
Merge remote-tracking branch 'aosp/master'
Merge remote-tracking branch 'aosp/master'
Merge branch 'master' of https://github.com/olibc/olibc