powerpc/64: Don't call trace_hardirqs_on() in prep_irq_for_idle()

Since commit a01353cf ("cpuidle: Fix ct_idle_*() usage"), the
cpuidle entry code calls trace_hardirqs_on() (actually
trace_hardirqs_on_prepare()) in ct_cpuidle_enter() before calling into
the cpuidle driver.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230406144535.3786008-2-mpe@ellerman.id.au

arch/powerpc/kernel/irq_64.c

@@ -348,9 +348,8 @@ EXPORT_SYMBOL(arch_local_irq_restore);
  * already the case when ppc_md.power_save is called). The function
  * will return whether to enter power save or just return.
  *
- * In the former case, it will have notified lockdep of interrupts
- * being re-enabled and generally sanitized the lazy irq state,
- * and in the latter case it will leave with interrupts hard
+ * In the former case, it will have generally sanitized the lazy irq
+ * state, and in the latter case it will leave with interrupts hard
  * disabled and marked as such, so the local_irq_enable() call
  * in arch_cpu_idle() will properly re-enable everything.
  */
@@ -370,9 +369,6 @@ __cpuidle bool prep_irq_for_idle(void)
 	if (lazy_irq_pending())
 		return false;
 
-	/* Tell lockdep we are about to re-enable */
-	trace_hardirqs_on();
-
 	/*
 	 * Mark interrupts as soft-enabled and clear the
 	 * PACA_IRQ_HARD_DIS from the pending mask since we