parisc: convert to generic compat_sys_ptrace

This patch does the compat_sys_ptrace conversion for parisc.
In addition it does convert the parisc ptrace code to use the
architecture-independent ptrace infrastructure instead of own coding.

Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>