timer_settime64

arm/disarm and fetch state of POSIX per-process timer

sys_timer_settime(timer_t timer_id, int flags, const struct __kernel_itimerspec *new_setting, struct __kernel_itimerspec *old_setting)

register	value
`a2`	409, the syscall number
`a6`	timer_t timer_id
`a3`	int flags
`a4`	const struct __kernel_itimerspec *new_setting
`a5`	struct __kernel_itimerspec *old_setting
`a2`	the return value

Then run syscall to enter the kernel.

Same syscall on other architectures