linux-libc-headers: ptrace.h: remove ptrace_peeksiginfo_args

linux-libc-headers: ptrace.h: remove ptrace_peeksiginfo_args

The addition of ptrace_peeksiginfo_args to the uapi in kernel commit
84c751bd [ptrace: add ability to retrieve signals without removing from a queue (v4)]
means that existing applications using glibc versions that define ptrace_peeksiginfo_args
in sys/ptrace.h will get duplicate structure definitions like:

    | In file included from /poky-master/build/tmp/work/i586-poky-linux/strace/4.8-r0/strace-4.8/process.c:66:0:
    | /poky-master/build/tmp/sysroots/qemux86/usr/include/linux/ptrace.h:58:8: error: redefinition of 'struct ptrace_peeksiginfo_args'
    |  struct ptrace_peeksiginfo_args {
    |         ^
    | In file included from /poky-master/build/tmp/work/i586-poky-linux/strace/4.8-r0/strace-4.8/defs.h:159:0,
    |                  from /poky-master/build/tmp/work/i586-poky-linux/strace/4.8-r0/strace-4.8/process.c:37:
    | /poky-master/build/tmp/sysroots/qemux86/usr/include/sys/ptrace.h:191:8: note: originally defined here
    |  struct ptrace_peeksiginfo_args
    |         ^
    | make[2]: *** [process.o] Error 1

Reverting to the previous status of not exporting this structure temporarily
fixes applications, until they can be adjusted to not mix sys/ptrace.h and
linux/ptrace.h includes.

(From OE-Core rev: 7c207e4c3c0e3b575c67a302b97b0dc700a8fc15)

Signed-off-by: Bruce Ashfield <bruce.ashfield@windriver.com>
Signed-off-by: Saul Wold <sgw@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>