Add definitions for PTRACE_GET_SYSCALL_INFO API

Add definitions for PTRACE_GET_SYSCALL_INFO API

Provide fallback definitions for PTRACE_GET_SYSCALL_INFO API.
Add very basic PTRACE_GET_SYSCALL_INFO support in the parser
of ptrace syscall.

* ptrace.h: Include <stdint.h>.
[!PTRACE_GET_SYSCALL_INFO] (PTRACE_GET_SYSCALL_INFO,
PTRACE_SYSCALL_INFO_NONE, PTRACE_SYSCALL_INFO_ENTRY,
PTRACE_SYSCALL_INFO_EXIT, PTRACE_SYSCALL_INFO_SECCOMP,
struct ptrace_syscall_info): Define.
* xlat/ptrace_cmds.in: Add PTRACE_GET_SYSCALL_INFO.
* process.c (SYS_FUNC(ptrace)): Handle it.