cpuidle: remove dead code from cpuidle_enter_state()

Checking for index < 0 is useless because the find_deepest_state()
function never really returns a negative value.

Since this hasn't been reported in over 9 years it's dead code, so
remove it.
Signed-off-by: Dhruva Gole <d-gole@ti.com>
Link: https://patch.msgid.link/20240821114250.1416421-1-d-gole@ti.com
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/cpuidle/cpuidle.c

@@ -228,10 +228,7 @@ noinstr int cpuidle_enter_state(struct cpuidle_device *dev,
 	if (broadcast && tick_broadcast_enter()) {
 		index = find_deepest_state(drv, dev, target_state->exit_latency_ns,
 					   CPUIDLE_FLAG_TIMER_STOP, false);
-		if (index < 0) {
-			default_idle_call();
-			return -EBUSY;
-		}
+
 		target_state = &drv->states[index];
 		broadcast = false;
 	}