Add the missing pieces in order to enable SECCOMP_FILTER on PowerPC
architectures, and enable this support.

Testing has been pursued using libseccomp with the latest ppc support patches
[1][2], on Freescale platforms for both ppc and ppc64. ppc64le support is
untested.

[1] https://groups.google.com/forum/#!topic/libseccomp/oz42LfMDsxg
[2] https://groups.google.com/forum/#!topic/libseccomp/TQWfCt_nD7c

v3:
- keep setting ENOSYS in syscall entry assembly when syscall tracing is disabled

v2:
- move setting ENOSYS from syscall entry assembly to do_syscall_trace_enter

Bogdan Purcareata (3):
  powerpc: Don't force ENOSYS as error on syscall fail
  powerpc: Relax secure computing on syscall entry trace
  powerpc: Enable HAVE_ARCH_SECCOMP_FILTER

 arch/powerpc/Kconfig           | 1 +
 arch/powerpc/kernel/entry_32.S | 7 ++++++-
 arch/powerpc/kernel/entry_64.S | 5 +++--
 arch/powerpc/kernel/ptrace.c   | 8 ++++++--
 4 files changed, 16 insertions(+), 5 deletions(-)

-- 
2.1.4