remove asm-generic/ptrace.h

From: Christoph Hellwig
Date: Wed May 01 2019 - 13:40:39 EST

Hi all,

asm-generic/ptrace.h is a little weird in that it doesn't actually
implement any functionality, but it provided multiple layers of macros
that just implement trivial inline functions. We implement those
directly in the few architectures and be off with a much simpler