PM / sleep: Drop unused `info' variable

Commit 32e8d689 (PM / sleep: trace_device_pm_callback coverage in
dpm_prepare/complete) removed all users of this variable but forgot to
remove the variable itself.
Signed-off-by: Thierry Reding <treding@nvidia.com>
[ rjw: Subject ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/base/power/main.c

@@ -1556,7 +1556,6 @@ int dpm_suspend(pm_message_t state)
 static int device_prepare(struct device *dev, pm_message_t state)
 {
 	int (*callback)(struct device *) = NULL;
-	char *info = NULL;
 	int ret = 0;
 
 	if (dev->power.syscore)
@@ -1579,24 +1578,17 @@ static int device_prepare(struct device *dev, pm_message_t state)
 		goto unlock;
 	}
 
-	if (dev->pm_domain) {
-		info = "preparing power domain ";
+	if (dev->pm_domain)
 		callback = dev->pm_domain->ops.prepare;
-	} else if (dev->type && dev->type->pm) {
-		info = "preparing type ";
+	else if (dev->type && dev->type->pm)
 		callback = dev->type->pm->prepare;
-	} else if (dev->class && dev->class->pm) {
-		info = "preparing class ";
+	else if (dev->class && dev->class->pm)
 		callback = dev->class->pm->prepare;
-	} else if (dev->bus && dev->bus->pm) {
-		info = "preparing bus ";
+	else if (dev->bus && dev->bus->pm)
 		callback = dev->bus->pm->prepare;
-	}
 
-	if (!callback && dev->driver && dev->driver->pm) {
-		info = "preparing driver ";
+	if (!callback && dev->driver && dev->driver->pm)
 		callback = dev->driver->pm->prepare;
-	}
 
 	if (callback)
 		ret = callback(dev);