Don't expose i386-only ptrace constants on amd64.  This broke gdb with libthread_db on amd64.
Don't expose i386-only ptrace constants on amd64.  This broke gdb with
libthread_db on amd64.

Reported by:	avg

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase