x86/entry/64: Trace irqflags unconditionally as ON when returning to user space

User space cannot disable interrupts any longer so trace return to user space
unconditionally as IRQS_ON.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Link: https://lkml.kernel.org/r/20200308222609.314596327@linutronix.de