debug/strace: pump version to 4.7 and 4.8

Pump version for strace to 4.7 and 4.8.
Add patch from strace mainline.


Work around conflict between <sys/ptrace.h> and <linux/ptrace.h>

Since glibc-2.18~39 <sys/ptrace.h> defines ptrace_peeksiginfo_args
which collides with <linux/ptrace.h>.

* configure.ac: Check for `struct ptrace_peeksiginfo_args' in
<sys/ptrace.h>.
* process.c: Work around potential conflict between <sys/ptrace.h>
and <linux/ptrace.h> by redefining ptrace_peeksiginfo_args.
* signal.c: Likewise.
* syscall.c: Likewise.
* util.c: Likewise.
http://sourceforge.net/p/strace/code/ci/0b4060f61f1bb101b5d8d084714b7d2feacdb199/

Signed-off-by: "Daniel Zimmermann" <netzimme@gmail.com>
Message-Id: <67b082cf1cdc8276eb4a.1385366288@haus-VirtualBox>
Patchwork-Id: 293842

This is a somewhat ordered TODO list:

Recurring tasks:

- update versions for every tools...

- update and/or upgrade all samples

Non-recurring tasks:

- update newlib (for enhanced bare metal)

  - confirm existing implementation on targets other than AVR32

  - try to make it generic, will help for uClibc++

- multilib

- Cygwin target (needs newlib)

  - so we can build toolchains that generate code for Windows/Cygwin

- Cygwin host

  - so we can build toolchains that run natively under Windows/Cygwin

- mingw32 target

  - so we can build toolchains that generate code for Windows/Win32

- mingw32 host

  - so we can build toolchains that run natively under Windows/Win32

    (without requiring Cygwin)

- uClibc++

  - see newlib, above

- uClinux

  - check whether we can use newlib under uClinux (?)