pci_get_device() will increase the reference count for the returned
pci_dev. We need to use pci_dev_put() to decrease the reference count
after using pci_get_device(). Let's add it.

Fixes: 59a3b3a8 ("cpufreq: AMD: Ignore the check for ProcFeedback in ST/CZ")
Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>