perf/x86/intel/uncore: Fix reference count leak in snr_uncore_mmio_map()

In the Linux kernel, the following vulnerability has been resolved:

perf/x86/intel/uncore: Fix reference count leak in snr_uncore_mmio_map()

pci_get_device() will increase the reference count for the returned

pci_dev, so snr_uncore_get_mc_dev() will return a pci_dev with its

reference count increased. We need to call pci_dev_put() to decrease the

reference count. Let's add the missing pci_dev_put().