Make sure that the PTRACE_... symbols are available for ppc/plt.c.

On a Fedora 12 x86_64 build/host box, this file was complaining about
PTRACE_PEEKTEXT being undefined. Adding in the "ptrace.h" include
fixed it.

Signed-off-by: Anthony Foiani <anthony.foiani@gmail.com>

reporter_name="Alexander BIGGA"

reporter_url="http://sourceware.org/ml/crossgcc/2008-06/msg00031.html"

reporter_comment=""