ACPI / utils: Drop reference in test for device presence

mainline inclusion
from mainline-5.1-rc2
commit 54e3aca84e57
category: bugfix
bugzilla: 13134
CVE: NA

-------------------------------------------------

When commit 8661423e ("ACPI / utils: Add new acpi_dev_present
helper") introduced acpi_dev_present(), it missed the fact that
bus_find_device() took a reference on the device found by it and
the callers of acpi_dev_present() don't drop that reference.

Drop the reference on the device in acpi_dev_present().

Fixes: 8661423e ("ACPI / utils: Add new acpi_dev_present helper")
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: NXiongfeng Wang <wangxiongfeng2@huawei.com>
Reviewed-by: NYang Yingliang <yangyingliang@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

drivers/acpi/utils.c

@@ -800,6 +800,7 @@ bool acpi_dev_present(const char *hid, const char *uid, s64 hrv)
 	match.hrv = hrv;
 
 	dev = bus_find_device(&acpi_bus_type, NULL, &match, acpi_dev_match_cb);
+	put_device(dev);
 	return !!dev;
 }
 EXPORT_SYMBOL(acpi_dev_present);