linux-imx

xtensa: move internal ptrace definitions from uapi/asm to asm

Stack frame layout diagram, kernel stack size and exception_handlers
offsets are used by the kernel and are not supposed to be accessible to
userspace. Move these definitions from uapi/asm/ptrace.h to asm/ptrace.h

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>